FIELD OF INVENTION

[001] The Present invention is related to medical drug delivery system & formulations used to treat and protect the central nervous system and methods of using those formulations. In particular, the invention relates to neuroprotective compositions and methods using those compositions to protect the brain or minimize lasting damage. The Present invention is related to formulation and method for enhance synaptic activity with triggering anterograde neurotransmission. More particularly, the present invention relates to a Drug delivery system and method for treatment of paraplegias, stroke, and brain death of a mammal. More particularly, the present invention related to drug delivery system and method thereof, for treatment of paraplegia, ischemic stroke, cerebral palsy and brain death by 10000 fold effect.

[002] The present invention relates to a newer concept by 10000 fold effect in treatment of ischemic stroke, paraplegias and brain death. The present invention particularly relates to a newer concept of treatment of paraplegia, ischemic stroke and brain death by 10000 fold effect. This 10000 fold effect is due to the affinity of nitric oxide receptors (NOR) to the nitric oxide (NO) at synaptic cleft. This NO is released from post synaptic membrane’s nitric oxide synthase (nNOS) at synaptic cleft by a nitric oxide donor (NOD). Thus the impulse is generated at the level of synaptic cleft or the impulse which was coming from presynaptic neuron is modified.

BACKGROUND & PRIOR ART

[003] Paraplegia is impairment in motor or sensory function of the lower extremities. It is usually caused by spinal cord injury or a congenital condition that affects the neural (brain) elements of the spinal canal. The area of the spinal canal that is affected in paraplegia is either the thoracic, lumbar, or sacral regions. Ischemia or ischemia is a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). [004] Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue. It also means local anemia in a given part of a body sometimes resulting from congestion (such

[005] A stroke is a medical emergency. Ischemic stroke is the most common type. It is usually caused by a blood clot that blocks or plugs a blood vessel in the brain. This keeps blood from flowing to the brain. Within minutes, brain cells begin to die. Another cause is stenosis, or narrowing of the artery. This can happen because of atherosclerosis, a disease in which plaque builds up inside your arteries.

[006] Brain death is the complete loss of brain function (including involuntary activity necessary to sustain life). It differs from persistent vegetative state, in which the person is alive and some autonomic functions remain.

[007] Nitric oxide (NO) signaling pathways mediate diverse physiological functions, including vasodilation and neurotransmission. Soluble guanylate cyclase (sGC), the primary NO receptor, triggers downstream signaling cascades by producing the second messenger cGMP.

[008] In neuroscience, retrograde signaling (or retrograde neurotransmission) refers more specifically to the process by which a retrograde messenger, such as anandamide or nitric oxide, is released by a postsynaptic dendrite or cell body, and travels "backwards" across a chemical synapse to bind to the axon terminal of a presynaptic neuron

[009] All the abbreviation and short form of terminology of the art used in this present disclosure are well known to the person skill in the art.

[0010] “10000 fold effect' term used as an artistic term to present drastically enhancement of theoretic efficacy for reverting back the physiological recovery is the basis of inventors’ new concept for physiological recovery in the treatment of paraplegia, ischemic stroke, cerebral palsy and brain death.

[0011] In neuroscience, glutamate refers to the anion of glutamic acid in its role as a neurotransmitter: a chemical that nerve cells use to send signals to other cells. It is by a wide margin the most abundant excitatory neurotransmitter in the vertebrate nervous system. It is used by every major excitatory function in the vertebrate brain.

[0012] The N-methyl-D-aspartate receptor (also known as the NMDA receptor or NMDAR), is a glutamate receptor and ion channel protein found in nerve cells. The NMDA receptor is one of three types of ionotropic glutamate receptors. The other receptors are the AMPA and kainate receptors. It is activated when glutamate and glycine (or D-serine) bind to it, and when activated it allows positively charged ions to flow through the cell membrane.

[0013] Nitric oxide synthases (NOSs) are a family of enzymes catalyzing the production of nitric oxide(NO) from L-arginine. NO is an important cellular signaling molecule. It helps modulate vascular tone, insulin secretion, airway tone, and peristalsis, and is involved in angiogenesis and neural development.

[0014] Intracarotid means“situated within, occurring within, or administered by entering a carotid artery”.

[0015] Intrathecal means “ introduced into or occurring in the space under the arachnoid membrane of the brain or spinal”

[0016] Sodium nitroprusside is “a red crystalline salt C ₅ FeN ₆ Na ₂ 0 administered intravenously as a vasodilator especially in hypertensive emergencies”

[0017] Some of related work in the prior art as follows:

[0018] Robert A. Herrmann & Wendy Naimark in US6780849B2 present a novel nitric-oxide releasing lipid molecules are provided which comprise a lipid molecule selected from (a) phosphoglycerides, (b) lipids having a sphingosine base as a backbone, (c) monoacylglyerols, (d) diacylglycerols, (e) glycosylacylglycerols, and (f) sterol compounds.

[0019] Valina L. DawsonTed M. DawsonEdythe D. LondonDavid S. Bredt & Solomon H. Snyder in US5266594A present Inhibitors of nitric acid synthase can be used to prevent neurotoxicity mediated through glutamate receptors. Nitric oxide synthase inhibitors can be used therapeutically in the treatment of vascular stroke and neurodegenerative disorders such as Alzheimer's disease and Huntington's disease.

[0020] Michael Chopp & Rui Zhang in US20020155173A1 presents a method of promoting neurogenesis by administering a therapeutic amount of a nitric oxide donor compound to a patient in need of neurogenesis promotion. Also provided is a compound for providing neurogenesis having an effective amount of a nitric oxide donor sufficient to promote neurogenesis. A nitric oxide compound for promoting neurogenesis is also provided.

[0021] David A. Wink, Jr.James B. Mitchell Angelo Russo Murali C. Krishnalngeborg Hanbauer Matthew B. Grisham Daniel & Neil Granger in US5789447A present a method for treating oxygen free radical induced tissue damage associated with ischemia reperfusion injury, wherein nitric oxide is delivered to target cells/tissues through the administration of a nitric oxide-containing compound that spontaneously releases nitric oxide under physiological conditions without requiring the presence of oxygen.

[0022] R. E. Garfield A. T. Balaban & W. A. Seitz in US5869539A present an emulsion comprising a perfluoro compound and nitric oxide and uses thereof. Methods of preparing such a nitric oxide source suitable for in vivo administration are described. These comprise dissolving nitric oxide in a perfluoro compound emulsion solvent. This method is useful for treating a mammal with nitric oxide by administering an emulsion comprising a perfluoro compound and nitric oxide. Exemplary conditions benefitting from appropriate nitric oxide treatment include hypertension, angina, preeclampsia and a wide variety of additional conditions, for example, those involving unduly restricted blood flow.

[0023] Until now due to the double edged sward like action of nitric oxide these researchers in prior art, were not able to work on NITRIC OXIDE after the initial phase of work of nitric oxide is over. Nobody gave any importance to iNOS and serum SOD. In the present invention, it is taken care of iNOS and serum SOD level by just waiting until their work has seized off in 5 days and then 10000 fold effect is employed to work. This gave us time period to work on and the powerful 10000 fold effect to work with.

[0024] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

[0025] As used in the description herein and throughout the claims that follow, the meaning of “a,”“an,” and“the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of“in” includes “in” and“on” unless the context clearly dictates otherwise.

[0026] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.

[0027] The use of any and all examples, or exemplary language (e.g.“such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0028] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

OBJECTIVE OF THE INVENTION

[0029] The primary objective of the present invention is to present a drug delivery system, formulation and method thereof for treatment of paraplegias, stroke, and brain death of a mammal. More particularly, the objective of the present invention is to present a drug delivery system, formulation and method thereof, for treatment of paraplegia, ischemic stroke, cerebral palsy and brain death by around 10000 fold effects. Another objective of the present invention is to solves the problems and enhance the therapeutic efficacy of the prior art techniques system, formulation and method for enhance synaptic activity with triggering anterograde neurotransmission.

SUMMARY

[0030] A Drug delivery system for the anterograde neurotransmission and for treatment for paraplegias, stroke or BRAIN DEATH of a mammal is presented in this present disclosure. This drug delivery system comprises a formulation of a Powdered- sodium nitroprusside, sterilely reconstituted with 0.2 to 0.4 mg/kg body weight dextrose with 50mg of the sodium nitroprussid. Then the mammal is hydrated. The administrating system is used for administration of Intracarotid- Sodium-Nitroprusside to the mammal, with simultaneous intravenous (IV) injection of 1 to 2 ml mephentermine to combat the ensuing sodium nitroprusside -related hypotension. The Administrating System administrate to the mammal , O.Olmg/kg of intracarotid -sodium -nitroprusside, up to a maximum of 0.01 to 0.02 mg/kg body weight , based on titration of hypotension. The Administrating System administrate the calculated dose as a bolus dose using a sterile technique, injected slowly over 3 to 5 minutes through a 20 to 25 G Lumbar puncture (LP) needle directly into the ipsilateral-carotid-artery of the mammal.

DETAIL DESCRIPTION

[0031] A Drug delivery system for the anterograde neurotransmission and for treatment for paraplegias, stroke or BRAIN DEATH of a mammal is presented in this present disclosure. This drug delivery system comprises a formulation of a Powdered- sodium nitroprusside, sterilely reconstituted with 0.2 to 0.4 mg/kg body weight dextrose with 50mg of the sodium nitroprussid. Then the mammal is hydrated. The administrating system is used for administration of Intracarotid- Sodium-Nitroprusside to the mammal, with simultaneous intravenous (IV) injection of 1 to 2 ml mephentermine to combat the ensuing sodium nitroprusside -related hypotension. The Administrating System administrate to the mammal , O.Olmg/kg of intracarotid -sodium -nitroprusside, up to a maximum of 0.01 to 0.02 mg/kg body weight , based on titration of hypotension. The Administrating System administrate the calculated dose as a bolus dose using a sterile technique, injected slowly over 3 to 5 minutes through a 20 to 25 G Lumbar puncture (LP) needle directly into the ipsilateral-carotid-artery of the mammal.

[0032] A method of for treatment of paraplegias, stroke, or brain death of a mammal is presented in the present disclosure herewith. This method comprises a administering to the mammal in need thereof a therapeutically effective amount of a Nitric Oxide Donor by either by injecting the Nitric Oxide Donor into the Cerebro Spinal Fluid OR By injecting into an artery just near to a requiring tissue, and bypassing the heart of the mammal. Then releasing of Nitric Oxide (NO) by the Nitric Oxide Donor from a Neuronal Nitric Oxide synthetase (nNOS) is performed at a postsynaptic membrane. The Nitric Oxide is taken off by Nitric Oxide Receptor (NOR), present at the presynaptic membrane. Then, the bonding of Nitric Oxide Receptor to Nitric Oxide (NO) occurs. Nitric Oxide Receptor - Nitric Oxide complex modules the Anterograde Neurotransmission (ANT).

[0033] Two mechanisms for acute-cases and one-mechanism for chronic- cases, which-are-interrelated, are being proposed for physiological recovery treatment of paraplegia, ischemic stroke, cerebral palsy and brain death by 10000 fold effect.

[0034] RETROGRADE-NEUROTRANSMISSION: (acute-cases)

[0035] During Normal excitatory impulse: at synaptic-level, glutamate activates NMDA-receptors, having Nitric-Oxide-Synthetase(NOS) on postsynaptic-membrane, for further propagation by calcium-calmodulin-complex. NITRIC-OXIDE(NO produced by NOS) travels backward across chemical synapse, binding to axon terminal (NO-receptor/sGC) of presynaptic-neuron, regulating- Anterograde-Neurotransmission( ANT) called Retrograde-

Neurotransmission(RNT).The-haem is the ligand binding site of NO receptor/sGC. The affinity of haem exhibits 10,000-fold excess for NO than Oxygen (THE=10,000-F OLD-EFFECT) completes in 20msec.

[0036] In Pathological conditions: normal-ANT, synaptic-activity including- RNT is-absent. NO-donor(SNP) release NO from NOS at postsynaptic-region. NO travels backward across a chemical-synapse to bind to the haem of NO- receptor at axon-terminal of a presynaptic-neuron, generates-impulse, as in normal-condition.

[0037] VASOSPASM: (acute-cases)

[0038] Perforators show vasospastic activity. NO vasodilates the perforators by NO cAMP pathway.

[0039] LONG TERM POTENTIATION (LTP): (chrome-cases)

[0040] NO-cGMP-pathway plays a role in LTP at many synapses throughout the CNS, and at neuromuscular junction. The LTP has been reviewed both generally and with respect to specific brain regions for memory/learning. LTP plays an important factor for relief from treatment of paraplegia, ischemic stroke, cerebral palsy and brain death by 10000 fold effect in chronic cases.

[0041] In recent years there is no modality which can revert back the physiological recovery except by giving time. This 10000 fold effect modality of reverting back the physiological recovery is the basis of inventors’ new concept for physiological recovery in the treatment of paraplegia, ischemic stroke, cerebral palsy and brain death.

[0042] Upto now, for physiological recovery:

[0043] PARAPLEGIA cases: After decompression of spinal cord and stabilization of vertebral body, inj METHYLPREDNISOLONE (NASCIS III) was given with questionable recovery, that too within 6 hours. We have this new concept of 10000 fold effect which acts on ANT via RNT and nNOS. This is given after 5 ^th day of well decompressed and stabilized spine. This can be given in an operated or nonoperated spinal paraplegia cases. Very highly effective within 2 hours thereafter incremental increase of recovery of motor power and sensory symptoms with bladder and bowel recovery, if any.

[0044] ISCHEMIC STROKE cases: Inj rTPA (RECOMBINANT TISSUE PLASMINOGEN ACTIVATOR) is been given within 4.30 hours for anterior circulation and 6 hours for posterior circulation ischemic strokes, impractical for developing countries and in most cases of developed countries too. We have this new concept of 10000 fold effect which acts on ANT via RNT and nNOS. This is given after 5 ^th day of ischemic stroke. This concept is highly effective and shows results within 2 hours thereafter incremental increase of recovery.

[0045] BRAIN DEATH cases: We have this new concept of 10000 fold effect which acts on ANT via RNT and Nnos and is highly effective to revert back the brain death criteria in various cases as this 10000 FOLD EFFECT activates the natural nNOS activity if given in 4 ^th ventricle and in quadrigeminal cistern. This concept is highly effective and shows results within no time thereafter incremental increase of recovery noted. [0046] PROCEDURE

[0047] A method of for treatment of paraplegias, stroke, or brain death of a mammal is presented in the present disclosure. This method comprises a administering to the mammal in need thereof a therapeutically effective amount of a Nitric Oxide Donor by either by injecting the Nitric Oxide Donor into the Cerebro Spinal Fluid OR By injecting into an artery just near to a requiring tissue, and bypassing the heart of the mammal. Then releasing of Nitric Oxide (NO) by the Nitric Oxide Donor from a Neuronal Nitric Oxide synthetase (nNOS) is performed at a postsynaptic membrane. The Nitric Oxide is taken off by Nitric Oxide Receptor (NOR), present at the presynaptic membrane. Then, the bonding of Nitric Oxide Receptor to Nitric Oxide (NO) occurs. Nitric Oxide Receptor - Nitric Oxide complex modules the Anterograde Neurotransmission (ANT).

[0048] More particularly, The natural nNOS is activated via an external NITRIC OXIDE DONOR (NOD). This NOD is put in cerebrospinal fluid, this releases NITRIC OXIDE (gaseous and highly diffusible) and thus clinical recovery achieved via 10000 fold effect Of NO on NOR. Here NO acts as an impulse generator and impulse moderator. This 10000 fold effect is highly effective after 5 ^th day because of the fact that the iNOS is destroyed also until then the SERUM SUPEROXIDE DISMUTASE (S-SOD LEVEL) comes to normal (iNOS and SOD both are hindrance to nor mal nNOS acitivity).

[0049] Examples according to the Present invention

[0050] For STROKE

[0051] NINDS study on thrombolytic therapy approved rTPA(recombinant-

Tissue-Plasminogen-activator) in 1995 for acute-ischemic-stroke. However, owing to its narrow window and its price, only a fortunate few eligible patients are able to receive it. Also low-frequency TCD (2-MHz-kHz) with rtPA-thrombolysis in acute-stroke and use of various stents have also been advocated but in acute stage. [0052] The early start of pulsations with physiological recovery (by electrical impulse generation) is the goal of any intervention performed on ischemic- penumbra region of brain.

[0053] For physiological recovery, we must attempt to understand the normal and abnormal impulses, synapses and the generation of action potential cascade that are well documented by clinical and nonclinical studies. Two mechanisms for acute, and one for chronic cases is being proposed here.

[0054] FOR-ACUTE(3-7 days)CASES-RETROGRADE-

NEUROTRANSMES SION -THEORY:

[0055] In normal excitatory-impulse at synaptic level, glutamate (released from presynaptic-membrane) activates NMDA receptor (associated with nitric- oxide-synthetase (NOS) from postsynaptic-membrane for further propagation by calcium-calmodulin-complex. NOS produces NO and then NO cloud at synapse thus bridging the microgaps. NO travels backward across this chemical synapse to bind to its receptor (NO receptor/sGC-soluble guanalyl cyclase), regulating anterograde-neurotransmission; this process is called “retrograde neurotransmission and allows neural circuits to create feedback- loops. NO- receptors(well equipped with a ligand-binding-site and a transduction- domain)differ in some interesting properties. The ligand-binding sit e(heme, such as hemoglobin in blood)when incorporated into the receptor-protein, exhibits >10,000-fold higher affinity for NO than for oxygen (THE 10,000 FOLD EFFECT) and is completed in 20 msec(9)decays in 200 msec . This reterograde- neurotransmission-like action of NO is also shown by carbon monoxide and platelet-activating factor.

[0056] ABNORMAL CONDITIONS

[0057] IMPULSES TOO-HIGH/TOO-LOW

[0058] NO can up or down regulate the oncoming-impulses. In conditions of high-intensity impulses such as schizophrenia and obsessive-compulsive disorder , NO downregulates the impulses; in conditions of low-intensity impulses such as depression with low-serotonin levels, NO upregulates the impulses.

[0059] IN THE ABSENCE OF IMPULSES

[0060] In cases with no impulse(Normal-Anterograde-Neurotransmission, including synaptic activity, with no Reterograde-Neurotransmission), NO-donors have shown promising results in generating impulses by increasing the frequency of spontaneous miniature EPSPs by NO via Reterograde-Neurotransmission in vitro in rats thus bypassing normal Anterograde-Neurotransmission This cascade relaxes the smooth-muscles of perforators.

[0061] b) FOR- ACUTE! 5-7 davsICASES- VASOSPASM-THEORY:

[0062] NO is a very potent vasodilator. SNP excels in emergency treatment of hypertension by vasodilation, which is instantaneous(onset within 30 seconds; peak in 2-5 minutes). Intrathecal-sodium-nitroprusside has been used in vasospasms induced by subarachnoid-hemorrhage. SNP acts on NOS present at the adventitial side of perforators, triggering NO release thus relaxes smooth muscles of perforators via cAMP pathway.

[0063] The impact of the intrathecal and intraventricular SNP in vasospastic cases on the larger-caliber vessels appears to be minimal, and the decreased cerebral circulation time indicates improved cerebral blood flow via microcirculation. Oral Sildenafil have been studied but only to relieve vasospasms caused by SAH. Studies on intra-arterial(for ergotism patients and intracarotid(for measurements of cerebral blood flow)were conducted on dogs cats and then on normal human beings who were subjected to DSA for other reasons

[0064] Various treatment options available are for salvaging the penumbra region and to relieve obstruction via thrombolysis, but no study for vasodilation of perforators at penumbra and to induce electrical impulses by EPSPs via the very potent RETEROGRADE-NEUROTRAN SMIS SION by bypassing the ANTEROGRADE-NEUROTRANSMISSION is available.

[0065] C) FOR-CHRONIC (>7 days) CASES: LTP (LONG-TERM- POTENTIATION)

[0066] Endocannabinoids-anandamide and 2-AG are primary-retrograde- messengers in brain and may also play an important role in retrograde-signaling in long-term-potentiation, which is crucial for memory &/or learning, as nitric-oxide. The NO-cGMP pathway plays a role in LTP at many synapses throughout the CNS and even at neuromuscular-junction.

[0067] This same principle of “generation of impulses from presynaptic- region to postsynaptic-region by highly-potent Reterograde-Neurotransmission (10,000-Fold-Effect), the vasodilation of arteriolar perforators and long-term- potentiation are the bases of the hypotheses for treating acute/chronic stroke cases.

[0068] FOR PARAPLEGIA

[0069] The functional recovery always remains in dark in well decompressed and stabilised spinal cord. Nitric oxide (NO) may prove promising results to achieve the physiological recovery of spinal cord by its 10000 fold effect via modulating neurovascular coupling at penumbra as shown in stroke cases in

MCAO rats’ model.

[0070] Neurovascular coupling (NVC), process by which increased neuronal activity in all neural tissues increases the local supply of oxygen (via several signalling pathways) and is always greater than the demand also called as functional hyperaemia, achieved by an integrated action of neurons, glial cells and blood vessels that form a‘neurovascular unit’. Disruption to NVC is a common process that underlies many brain disease states. Nitric oxide (NO) is a multimodal neurotransmitter, gaseous molecule synthesised from L-arginine by the enzyme nitric oxide synthase (NOS) active in the signalling pathways that acts at NVC of global cerebralVspinal cord vessels and local neural tissue thus important for autoregulation. [0071] Penumbra (local vasospasm, hypovascularity and diminished impulse generation around the stroke core) is a well-known entity where NYC gets deranged in brain stroke or spinal cord insult cases. In experimental spinal cord injury, diminished blood is well demonstrated in laboratory both by scanning and transmission electron microscopy. As penumbra in stroke cases is salvageable (not the core) so also in spinal cord, if vascularity and generation of impulse can be employed by any means. This local spinal penumbra can also be accidently reproduced iatrogenic after spinal operations.

[0072] So to overcome this grave problem of physiological recovery by generation of impulse and increased blood supply we have to understand the localised NYC, synapses, the normal/abnormal impulses and the generation of action potential cascade. Exact mechanism is still unknown but two mechanisms for acute, and one for chronic cases is being proposed here.

[0073] a) FOR ACUTE CASES - RETROGRADE

NEUROTRANSMIS SION-(RNT) :

[0074] In normal impulse (anterograde neurotransmission -ANT) at synaptic level, glutamate is released from presynaptic membrane that activates NMDA receptor at postsynaptic-membrane for further propagation by calcium- calmodulin-complex. NMDA also activates NOS that releases NO which travels back in the synaptic cleft, forms a NO cloud across chemical synapse to bind with NO receptor (NOR)/sGC (soluble guanylyl cyclase) of axon terminal of presynaptic neuron then regulates ANT, this process is called “retrograde- neurotransmission” (RNT) , allowing neural circuits to create feedback loops so called as chemical neuroregulation. NORs are well equipped with a ligand binding site and a transduction domain.

[0075] The ligand-binding-site (haem- like haemoglobin of blood) when incorporated into the receptor protein, exhibits >10,000-fold excess affinity for NO than Oxygen (of alveoli) (the 10,000-fold-effect), completes in 20msec and determined by Pico Nano Second Absorption Spectroscopy (PNSAS) which may contribute to beneficial effects in NVC disruption diseases. NO can up or down regulate the oncoming impulses in a normal impulse. [0076] Three isoform of NOS exist: endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), and inducible nitric oxide synthase (iNOS).

[0077] eNOS (neuroprotective) is expressed in the vascular endothelium and choroid plexus, plays a role in preserving and maintaining the brain's microcirculation reducing smooth muscle proliferation, inhibiting platelet aggregation and leukocyte adhesion and migration.

[0078] nNOS (neuroprotective) derived from nNOS acts as an important neurotransmitter associated with neuronal plasticity, memory function, regulation of central nervous system blood flow, transmission of pain signals and neurotransmitter release.

[0079] iNOS (neurotoxic) is expressed in macrophages, glial cells and tumour cells in response to pro-inflammatory cytokines or endotoxin and unlike eNOS and nNOS it is not expressed unless induced by cytokines or other agents. It can produce a large amount (100-1000 times greater) of NO in relation to eNOS and nNOS, due to its independence from calcium dependent mechanisms for activation. After induction, iNOS continuously produces NO until the enzyme is degraded ²⁷ . iNOS peak concentrations occur around 1-2 days after the injury. Patients with higher levels went on to have a worse outcome which proves the version“NO is a double edged sward”.

[0080] eNOS is neuroprotective whereas iNOS is neurotoxic this difference is due to differences in timing, spatial location and concentration of NO generated by each isoform.

[0081] Overall, the balance of evidence is in favour of iNOS activity being harmful in the patient population, and therefore our study’s superfusion of ITSNP was done 5 ^th day post paraplegia onwards.

[0082] ABNORMAL CONDITIONS

[0083] IMPULSE TOO-HIGH OR TOO-LOW

[0084] In conditions of high-intensity-impulse like Schizophrenia and

Obsessive compulsive disorder, NO down-regulates the impulse; in conditions of low-intensity-impulses like Depression with low-serotonin levels, NO up- regulates the impulse.

[0085] IN ABSENCE OF IMPULSE

[0086] In cases with diminished or no impulse, NO-donors (NODs) have shown promising result in generating an impulse by NO via RNT in vitro in animal. The study by O-Dell-et-al (1991) on rat’s tissue showed that exogenous NODs increase frequencies of spontaneous miniature EPSPs. NO travels backward across a chemical synapse, binding to axon terminal (NOR/sGC) of presynaptic-neuron, acts as impulse-generator, as in normal condition, thus bypassing the normal ANT ) determined by PNSAS , exact mechanism still to be completely understood.

[0087] b) FOR ACUTE CASES -VASODILATOR Y EFFECT ON VASOSPASM

[0088] SNP acts on NOS present on the adventitial-side of the perforators, triggering NO-release. In nerve cells, NO switches on the associated guanylylcyclase (cAMP) activity, is a very potent-vasodilator. SNP excels in emergency treatment of hypertension by vasodilation action which is instantaneous (onset-within 30seconds; peak in 2-5minutes). As stated earlier vasospasm, demonstrated after experimental spinal-cord injury in laboratory by scanning and transmission-electron-microscopy. NO vasodilates the spinal arterioles (in resting and compressed states of the spinal-cord causing gush of blood into spinal-cord.

[0089] ITSNP has been used in treatment of refractory vasospasm due to subarachnoid-hemorrhage (S AH) acts at microcirculation.

[0090] cl FOR CHRONIC CASES 021 davsl-LTP (LONG TERM POTENTIATION)

[0091] LTP is meant for memory and learning The endocannabinoids anandamide and 2-AG are the primary retrograde messengers in the brain and may also play an important role in retrograde signaling in long-term-potentiation (LTP), as is nitric-oxide . NO-cGMP pathway plays a role in LTP at many synapses throughout the CNS, and even at the neuromuscular junction. The LTP has been reviewed both generally and with respect to specific brain regions. This mode of action of NO is the basis of hypothesis of authors to treat chronic cases who presented 21 days post paraplegia.

[0092] The disruption to NYC is reversible in the presence of an exogenously administered NOD or even by hypothermia. Locally NO can be provided by direct NO (inhaled NO) or systemic NOD.

[0093] Inhaled NO is neuroprotective in the developing brain, with reduction in the size of excitotoxic and ischaemic lesions in rats via Cellular mechanisms such as S-nitrosylation of proteins and effects on mitochondrial respiration.

[0094] NODs :

[0095] Oral NODs are a phosphodiesterase type 5 (5-PGE) inhibitor e.g., sildenafil, increases blood flow and has neuroprotective effects in the rat model of hypoxic-ischaemic brain injury ⁶³ .

[0096] Injectable NODs after IV administration causes systemic effects like Cardiovascular instability (sodium nitroprusside-SNP requires oxygen to provide NO locally) and glyceryl trinitrate (GTN) or are with minimal effects on the systemic vasculature after IV administration like sodium nitrite (it doesn’t require oxygen to provide NO locally).

[0097] We used intrathecal SNP (ITSNP). In the present study, we investigated the time course, dose and duration of the protective effect of post treatment with the NOD (ITSNP) in partial paraplegia cases since complete paraplegia has disrupted spinal cord due to contusion. The availability of drug, to be tested, at remote areas in developing countries, is one of the hindrances to this study so we chose easily available and cheaper drug that is SNP and not sodium nitrite. Dose also coincided with the previous studies of use of SNP in refractory vasospasm conditions used in humans.

[0098] This same Principle of “generation-of-impulses from postsynaptic- region to presynaptic-region by the very potent RNT (10,000-FOLD-EFFECT) thus bypassing the normal ANT cascade, vasodilatation of arteriolar perforators hypothesis to treat acute (5 to 21 days) and LTP for chronic (>21 days) paraplegia cases is the basis in paraplegia cases. [0099] FOR BRAIN DEATH

[00100] Understanding of brain death’s etiopathogenesis has undergone a giant stride in past decades, so as the further management, from simple surfeit waiting for natural death to medical fraternity fostering stem cell transplantations in brain or various organ transplantations. Even doctors treat the patients frantically either from relevant court cases or due to loss of any further hope of survival. This can only be eulogized and pertinent if the brunt of brain death cases be minimized and interventional therapeutic measures’ aggrandizement noted which can show a ray of light in future.

[00101] Primary or secondary brain deaths are associated with ischemia to some part of the brain and brain stem due to acute neurogenic shock or a cortical tissue disruption. The ischemia further leads to local axonal reflex stimulation which causes local perforators to go in spasm & further exaggerating the anoxic damage, in the form of neuropraxia along with infarcted area.

[00102] Until now none of the studies were directed towards the vasodilation of vasospasm of the perforators. Our study is directed towards the relieving of arteriolar perforator’s vasospasm.

[00103] Vasospasm has been conclusively demonstrated after experimental spinal cord injury in laboratory both by scanning and transmission electron microscopy . In brain, Nitric oxide (NO) has a stellar role in neurotransmitter modulation, retrograde neurotransmission, synaptic plasticity and a very potent vasodilator. The vasodilator effect of SNP is known since the evolution of emergency treatment of hypertension. The perforators are having Nitric Oxide Synthetase (NOS) which is present on the outer border or the adventitial side on which sodium nitroprusside (SNP) acts, causing release of NO. NO is involved in vasoregulation by maintaining spinal arteriolar tone in resting and compressed states of the spinal cord , which vasodilates the perforators causing gush of blood into the spinal cord, is rapid (onset of action in 30 seconds and peak in 2-5 mints) , this reverts the spinal cord function razzmatazztic. [00104] This same Principle has been utilized by the authors in brain death cases too. A single intrathecal superfusion of SNP via transoptic canal route for quadrigeminal cistern superfusion and cisternal puncture for IV ventricular superfusion with SNP opens up the arteriolar perforators or causes the potent retrograde transmission function by releasing NO. Thereby gush of blood in ischemic area of brain and brain stem or the very potent retrograde transmission function which is responsible for immediate onset of action and the mesmerizing effect.