Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Synthetic substance P has been discovered to stimulate significantly the formation of dopa in the limbic, striatum, hemisphere and diencephalon regions of the brain and the lower brain stem. There was no effect upon 5-hydroxytryptophan formation or on tryptophan or tyrosine levels. After inhibition of monoamine synthesis by N'-(DL-SERYL)-N2-(2, 3, 4-trihydroxybenzyl)hydrazine, substance P significantly accelerated the disappearance of dopamine, noradrenaline and 5-hydroxytryptamine. Substance P appears to stimulate monoaminergic neurons in the brain and to serve as an excitatory transmitter in nerve terminals impinging upon dopaminergic cell bodies. A similar stimulation of noradrenaline and 5-hydroxytryptamine indicate a similar transmitter role for noradrenergic and serotonergic neurons. These data strengthen questions about the possible clinical influence of substance P in disease states involving monoaminergic mechanisms including Parkinsonism and schizophrenia.
 ...
PMID:Effect of synthetic substance P on monoaminergic mechanisms in brain. 0 76

The effects of GABA, substance P and dopamine on the release of newly synthesized 3H-5-HT were investigated, using slices of rat substantia nigra superfused with L-3H-tryptophan in vitro. GABA (50 micron) had no inhibitory effect on the potassium-evoked-release of 3H-5-HT. Substance P (50 micron) and eledoisin (50 micron) stimulated the spontaneous release of 3H-5-HT. This effect seems to be indirect and is possibly mediated by dopaminergic neurones, since the dopamine antagonist drug alpha-flupenthixol (1 micron) abolished the substance P-evoked release of 5-HT. Furthermore, it was found that substance P (10 micron) stimulated 3H-dopamine release from nigral slices in vitro and the dopaminergic agonist apomorphine (50 micron) also stimulated 3H-5-HT release. Substance P may, therefore, activate nigral dopaminergic neurones which then release dopamine from their dendrites. The release of dopamine may in turn stimulate 5-HT release from terminals of the raphe-nigral pathway.
 ...
PMID:Effects of GABA, dopamine, and substance P on the release of newly synthesized 3H-5-hydroxytryptamine from rat substantia nigra in vitro. 71 84

We have examined the action of the thrombin receptor-derived polypeptide, S42FLLRNPNDKYEPF55 (TRP 42-55), in rat and guinea pig aortic rings and helical arterial strips, and we have compared the actions of the peptide with those of thrombin. In rat preparations, both TRP 42-55 and thrombin caused a concentration-dependent endothelium-dependent relaxation that was blocked by N omega-nitro-L-arginine methyl ester; the relaxation response of the intact rat aortic strip preparation to concentrations of the peptide in the range 30-60 micrograms/mL (17-34 microM) was equivalent to the response to 0.03-0.1 U/mL of thrombin (about 0.3-0.9 nM), yielding a potency ratio (TRP 42-55:thrombin) of about 38,000:1. In contrast with the complete desensitization of thrombin-treated rat aortic preparations to a second administration of the enzyme, the rat aortic tissue was not desensitized by repeated exposures to TRP 42-55 and remained responsive to the peptide even after treatment of the tissue by thrombin. In contrast with the rat aortic tissue, in either intact or endothelium-free guinea pig aortic preparations both TRP 42-55 and thrombin caused a concentration-dependent endothelium-independent contraction. The contractile action of 60 micrograms/mL of receptor peptide (34 microM) in guinea pig aortic strip preparations was equivalent to the contractile action of 0.1-0.3 U/mL thrombin (0.9-3 nM), yielding a potency ratio of about 17,000:1. In guinea pig aortic preparations with an intact endothelium that were precontracted with noradrenaline, neither thrombin nor TRP42-55 caused relaxation, whereas substance P did so.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Vascular actions of thrombin receptor peptide. 133 53

To discover a novel and low molecular weight substance P (SP) antagonist we postulated that the essential binding domain of peptide ligands was only a small portion in the whole structure. On the basis of this assumption, we selected the known octapeptide SP antagonist D-Pro-Gln-Gln-D-Trp-Phe-D-Trp-D-Trp-Phe-NH2 (1) as a lead and synthesized its fragment tripeptides which were evaluated for their activity to block 3H-SP binding on guinea pig lung membranes. The protected tripeptide N alpha-[N alpha-[N alpha-(tert-butyloxycarbonyl)-L-glutaminyl]-N1-formyl-D-tryptophyl]- L-phenylalanine benzyl ester [Boc-Gln-D-Trp(CHO)-Phe-OBzl (4a)], corresponding to the Gln-D-Trp-Phe part of 1, exhibited 7-fold potent inhibitory activity in comparison with 1. Studies on structure-activity relationships revealed that the D-tryptophan, L-phenylalanine, and benzyl ester were quite important to maintain the high binding affinity. It was also indicated that 4a antagonized the SP-induced contraction of isolated guinea pig trachea strips (IC50 = 4.7 x 10(-6) M).
 ...
PMID:Studies on neurokinin antagonists. 1. The design of novel tripeptides possessing the glutaminyl-D-tryptophylphenylalanine sequence as substance P antagonists. 137 65

Two undecapeptide substance P (SP) analogues, Spantide I and Spantide II, were tested for their capacity to block the contractile effect of SP on the guinea pig isolated taenia coli and the contractile effect of electrical stimulation of the rabbit isolated (and atropinized) iris sphincter, and for their capacity to mobilize histamine from rat isolated peritoneal mast cells. Spantide I and Spantide II have one feature in common, namely D-tryptophan in positions 7 and 9. Spantide I: D-Arg, Pro2, Lys3, Pro4, Gln5, Gln6, D-Trp7, Phe8, D-Trp9, Leu10, Leu11-NH2. Spantide II: D-NicLys1, Pro2, 3-Pal3, Pro4, D-Cl2Phe5, Asn6, D-Trp7, Phe8, D-Trp9, Leu10, Nle11-NH2. Both Spantide I and II were found to be competitive antagonists to SP on the taenia coli and to be capable of blocking the electrically induced non-cholinergic contraction of the iris sphincter. Spantide II had higher pA2 value (taenia coli) than Spantide I, 7.7 versus 7.0, and higher pIC50 value (blockade of tachykinin-mediated neurotransmission in iris sphincter), 6.0 versus 5.1. Both Spantide I and II mobilized histamine from rat peritoneal mast cells but Spantide II was less effective. Spantide I and II were tested for antagonistic specificity. Both blocked contractions of the taenia induced by SP and neurokinin A. In the concentration used, Spantide II in addition blocked the response to neurokinin B. The contractions induced by carbachol, 5-hydroxytryptamine, histamine and prostaglandins (F2 alpha and E1) were not affected; the contractile response to bombesin was inhibited by Spantide I but not by Spantide II.
 ...
PMID:Spantide II, a novel tachykinin antagonist having high potency and low histamine-releasing effect. 170 95

The classical approach used in the development of substance P (SP) antagonists, i.e. the introduction of multiple D-tryptophan (D-Trp), was successfully extended to neurokinin A (NKA). Thus, a new NK-2-selective tachykinin receptor antagonist, namely [Tyr5, D-Trp6,8,9, Arg10]NKA-(4-10), was developed that had pA2 values of 5.2, 7.9 and 4.9 in three monoreceptor in vitro assays for NK-1, NK-2 and NK-3 tachykinin receptors, respectively.
 ...
PMID:A highly selective NK-2 tachykinin receptor antagonist containing D-tryptophan. 215 94

Serotoninlike immunoreactivity was examined by the fluorescein-isothiocyanate-labeled secondary antibody technique in the lateral eye and brain of Limulus. Endogenous serotonin was measured with high-performance liquid chromatography and electrochemical detection. The synthesis of [3H]serotonin from [3H]tryptophan was measured in the presence and absence of reserpine. Fibers with serotoninlike immunoreactivity were found in the proximal stalks of the corpora pedunculata, in the neuropil of the central body, in the neuropils of the visual centers (lamina, medulla, and ocellar ganglion), in the optic tract that connects the ocellar ganglion with the posterior medial medulla, and in the central neuropil of the brain. Immunoreactive somata were found in four groups in the brain. Up to 50 somata were scattered through each side of the dorsal medial group that lies centered on the dorsal surface within the curve of the central body. These neurons innervate the central body neuropil and send processes into the central neuropil. Three or four reactive somata formed the ventral pole of each medullar group. These may provide the innervation of the proximal stalk of the corpora pedunculata. Five to ten reactive neurons were observed anteriorly in the ventral posterior lateral group #2 on each side that send processes into the central neuropil. Ten to 15 reactive somata were found on either side of the midline in the dorsal anterior part of the ventral medial group that contribute processes to the central neuropil. The remainder of the brain was not immunoreactive. No immunoreactive fibers or somata were found in the lateral eye or in the lateral optic nerve. Serotoninlike and substance P-like immunoreactivities were not found to be colocalized anywhere in the brain. Significant amounts of endogenous serotonin were detected in the lamina and medulla whose neuropils are rich in immunoreactive fibers and in the central body and dorsal medial group that are also rich in immunoreactive somata and fibers. No endogenous serotonin was detected in either the lateral eye or the lateral optic nerve. The lamina, medulla, and central body and dorsal medial group also synthesized and stored [3H]serotonin from [3H]tryptophan. It is likely that serotonin is a neurotransmitter in the brain, but not in the lateral eye of the horseshoe crab. In particular, it appears that serotoninergic neurons may play a role in central visual processing.
 ...
PMID:Immunoreactivity in Limulus. II. Studies of serotoninlike immunoreactivity, endogenous serotonin, and serotonin synthesis in the brain and lateral eye. 242 96

Using the "Bi-Digital O-Ring Test Molecular Identification and Localization Method," one can identify and localize minute amounts of bioactive substances (including neurotransmitters), micro-organisms, toxic substances, or drugs, and, in addition, one can non-invasively image normal organs as well as screen for and image the distribution of specific types of cancer of specific internal organs without using any expensive instrumentation. One can also use this method to perform a qualitative analysis of neurotransmitters, neuromodulators, and hormones on different parts of the imaged organs. The molecule or substance being investigated is compared with a minute amount of a pure control reference substance, and if the substance identical to the control reference substance exists, then the electro-magnetic waves emitted by the identical substance will produce an electro-magnetic resonance phenomenon with the electro-magnetic waves of identical resonance frequency emitted by the control reference substance, and this resonance phenomenon is hypothesized to be the basis of the "Bi-Digital O-Ring Test Molecular Identification and Localization Method." The following substances have been used as control reference substances to identify and localize identical substances in vitro and in vivo: pure neurotransmitters (e.g. serotonin, beta-endorphin, methionine-enkephalin, norepinephrine, dopamine, L-dopa, substance P, etc.), as well as L-tryptophan and L-tyrosine; cholesterol; steroid hormones (including aldosterone, corticosterone, cortisol, progesterone, testosterone, etc.); peptide hormones; microscopic slides of normal organs; microscopic slides of specific cancer cells of specific organs (e.g. adenocarcinoma of the head of the pancreas, adenocarcinoma of the descending colon, etc.); microscopic slides of pure micro-organisms; toxic substances (e.g. lead, mercury, KCN); drugs (including non-steroidal anti-inflammatory drugs, antibiotics, beta-blockers, calcium channel blockers, etc.); and antibodies against specific substances or micro-organisms. An intensive network of serotonin and L-tryptophan was discovered, by using the "Bi-Digital O-Ring Test Molecular Identification and Localization Method," in different parts of the body. In general, in painful areas, frequently serotonin is markedly reduced, L-tryptophan is markedly increased, and substance P is markedly increased, while in non-painful areas, serotonin is markedly increased, L-tryptophan is markedly decreased, and substance P is markedly decreased.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:"Bi-digital o-ring test molecular identification and localization method" and its application in imaging of internal organs and malignant tumors as well as identification and localization of neurotransmitters and micro-organisms--Part 1. 287 19

Using voltage-time-dependent negative resistance characteristics of Voltage-Current curves of excitable cell membranes estimated without using artificial voltage clamp method, the author made a quantitative analysis of excitability of cell membranes and different conditions of transmembrane action potentials as a bias voltage to the negative resistance of the excitable cell membrane. The pacemaker cells were classified as "Astable Oscillators" and nonpacemaker excitable cells as "Monostable Oscillators," and application of a rapidly changing electromagnetic field to the cells was analyzed as a means of stimulating the cells. The understanding of the 10 essential electrical parameters is highly desirable for safe and effective electrical stimulation. Among these, emphasis was placed on the often neglected, important electrical parameters of "output impedance" of stimulation pulse wave complexes for + and - polarity components, as well as the importance of capacitive current (Ic = C.dV/dt) which depends on rise time as well as fall time of the stimulation pulse wave, and undesirable side effects of electrolysis phenomena due to excessive D.C. current. The difference and similarity between TENS (Transcutaneous Nerve Stimulation) and TES (Transcutaneous Electrical Stimulation), TENMS (Transcutaneous Electrical Nerve and Muscle Stimulation) or TMS (Transcutaneous Muscle Stimulation) was discussed. The author's clinical study indicated that effective TES (TENMS)--characterized by effective muscle contraction without creating pain with a pulse repetition rate approximately the same as the heart rate of the individual--can often give superior beneficial effects in improvement of micro-circulation and subsequent relief of pain and other symptoms compared with TENS that creates stimulation of large diameter sensory nerve fibers without creating significant muscle contraction. Such improvement is often accompanied by the abolishment of the pain with disappearance of local substance P and increase in local serotonin with disappearance of local L-tryptophan.
 ...
PMID:Basic electrical parameters for safe and effective electro-therapeutics [electro-acupuncture, TES, TENMS (or TEMS), TENS and electro-magnetic field stimulation with or without drug field] for pain, neuromuscular skeletal problems, and circulatory disturbances. 289 68

The onset of therapeutic effectiveness of carbamazepine is generally very rapid in the treatment of seizure and paroxysmal pain disorders, shows some lag in the treatment of mania, and exhibits the longest lag in depression. These time course variations may indicate that different mechanisms underlie the efficacy of carbamazepine in the differential neuropsychiatric syndromes. Biochemical and pharmacological data suggest that the anticonvulsant effects of carbamazepine are related to "peripheral-type" benzodiazepine and alpha 2-noradrenergic receptor systems and to its ability to stabilize sodium channels. GABAB (baclofen-like) actions appear to be involved in antinociceptive, but not anticonvulsant, effects. The relatively acute time course of antimanic efficacy may be related to the above-mentioned mechanisms or to other effects related to systems postulated to be altered in the manic syndrome. These effects might include carbamazepine's ability to increase acetylcholine in the striatum, decrease probenecid-induced levels of CSF homovanillic acid (HVA) in man and dopamine turnover in animals, decrease CSF norepinephrine in manic patients, inhibit adenylate cyclase activity (in response to norepinephrine, dopamine, adenosine, or ouabain), decrease GABA turnover, or act as a vasopressin agonist. Efficacy in depression may be related to actions in man that take time or chronic drug administration to develop, such as increases in plasma tryptophan, decreases in CSF somatostatin, decreases in thyroid indices, and increases in urinary free cortisol excretion and, in animals, increases in substance P sensitivity and increases in brain adenosine receptors. The ability of carbamazepine to block the development of lidocaine- and cocaine-induced seizures also requires chronic administration, suggesting that these seizure models may provide a unique perspective for understanding mechanisms of time-dependent effects.
 ...
PMID:Time course of clinical effects of carbamazepine: implications for mechanisms of action. 328 May 60


1 2 3 4 5 6 7 8 Next >>