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

[Tyr8]-substance P, an undecapeptide having the structure Arg-Pro-Lys-Pro-Gln-Gln-Phe-Tyr-Gly-Leu-Met-NH2, has been synthesized by the solid-phase technique on a Beckman automatic peptide synthesizer, appropriately purified and biologically characterized. At twice the dosage, [Tyr8]-substance P showed the same biological activity response as synthetic substance P for stimulation of contraction of the isolated guinea pig ileum and for decrease in the systemic blood pressure of dogs. On the dog's blood pressure, no qualitative differences were observed, but on the isolated gut, the Tyr8 analog gave a more gradual increase in the muscle tone than synthetic substance P. [Tyr8]-substance P released, in vitro, the luteinizing and follicle-stimulating hormones at a very high dosage but did not release growth hormone, prolactin, or thyrotropin.
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PMID:Synthesis and some biological activities of the tyrosine-8 analog of substance P. 124 14

Gut-associated lymphoid cells are modulated by several gut hormones. We postulated that lymphokine-associated-killer (LAK) cell cytotoxicity of lymphocytes isolated from the gut mucosa may be increased by substance P (SP). Intestinal lamina propria mononuclear cells (LPMC) and colonic cancer cells were isolated from operative specimens by successive mechanical and enzymatic dissociation methods. Effector LAK cells were induced by culturing LPMC with recombinant interleukin-2 at a concentration of 250 U/ml. Substance P (10(-5) M) was added to the culture medium. Targets consisted of fresh colon cancer cells, HT-29 (cultured human colon cancer cell line), and control cell lines. After 4 days of incubation, cytotoxicity was measured using a 4-h 51Cr release assay. LAK cells alone showed moderate cytotoxicity against HT-29 and none against fresh colon cancer cells. LAK cells generated in the presence of substance P showed moderate cytotoxicity against HT-29 and strong cytotoxicity against fresh colorectal cancer cells. The percentage of cytotoxicity +/- SEM at various effector to target ratios was [(*) denotes P < 0.05 compared with above]: [table: see text] We conclude that substance P significantly increases LAK cell cytotoxicity against fresh colon cancer cells, but not against cultured cells.
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PMID:Substance P increases in vitro lymphokine-activated-killer (LAK) cell cytotoxicity against fresh colorectal cancer cells. 127 74

Tachykinins (TK) are family of peptides including substance P (SP), substance K (SK) and neuromedin K (NK) that have been found in the nerves of the gastrointestinal tract and proposed to act as neurotransmitters to affect the motor, secretory and circulatory functions of the gut, but little is known about their action on the pancreas. In this study three series of tests were carried out to determine the action of SP, SK and NK on pancreatic secretion in conscious dogs and amylase release from the dispersed rat pancreatic acini and to correlate the alterations in pancreatic secretory and circulatory effects of TK in anesthetized dogs. SP, SK and NK infused i.v. in graded doses (0.12-1.0 microgram/kg per h) in conscious dogs stimulated pancreatic protein outputs reaching, respectively, 38% and 23% of the maximal response to CCK (40 pmol/kg per h). HCO3- outputs were also significantly increased but the highest response did not exceed about 5% of secretin (328 pmol/kg per h) maximum. Cholinergic blockade by atropine abolished the pancreatic responses to tachykinins. When added at various concentrations (10(-11)-10(-7) M) to the incubation medium of rat dispersed pancreatic acini, SK, SP and NK increased in concentration-dependent manner the release of amylase from the resting pancreatic acini and augmented the enzyme release induced by CCK-8 and by urecholine. In anesthetized dogs infused with a background dose of secretin (82 pmol/kg per h), addition of SP, SK and NK caused an immediate and dose-dependent increase in the pancreatic blood flow, oxygen consumption and pancreatic secretion accompanied by a dose-dependent decrease in arterial blood pressure. This study shows that TK are potent pancreatic circulatory stimulants and moderate secretagogues both in vivo and in vitro, acting, at least in part, via cholinergic pathway.
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PMID:Role of tachykinins in the control of pancreatic secretion and circulation. 128 Apr 85

The distribution of neurotensin-, substance P-, gastrin/cholecystokinin/carerulein- and bombesin-like immunoreactivities has been studied in the gut of the tilapia (Oreochromis mossambicus) and the goldfish (Carassius auratus) using immunohistochemistry and radioimmunoassay; the electrophysiological effects of these peptides on the intestinal epithelium were also examined with the Ussing-type chamber technique. Neurotensin- and gastrin/cholecystokinin/caerulein-like immunoreactivities were present in endocrine cells in both species. Substance P- and bombesin-like immunoreactive endocrine cells were present in the intestine of the tilapia. Neurotensin-like immunoreactivity was observed in varicose fibers and nerve cell bodies in the muscle layers and myenteric plexus of both species, whereas nerve fibers showing substance P-like immunoreactivity were found in the goldfish only. Using radioimmunoassays, neurotensin- and gastrin/cholecystokinin/caerulein-like immunoreactive materials were detected in intestinal extracts of both species. The amounts of substance P- and bombesin-like material were below detection level. The ion selectivity of the intestinal epithelium of both species was modulated by exogenously applied neurotensin. This effect was blocked by tetrodotoxin in the tilapia but not in the goldfish. In the tilapia, neurotensin may act via stimulation of a cAMP-dependent increase of the Cl- conductance of the tight junctions, whereas in the goldfish, neurotensin induced, via an unknown messenger, a transient decrease of the cation selectivity without a decrease in the resistance. Substance P, cholecystokinin, and bombesin were without effect on the electrophysiological characteristics of the epithelium.
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PMID:Neurotensin, substance P, gastrin/cholecystokinin, and bombesin in the intestine of the tilapia (Oreochromis mossambicus) and the goldfish (Carassius auratus): immunochemical detection and effects on electrophysiological characteristics. 128 77

Loose ligation of the sciatic nerve with 4-0 chromic gut sutures in rats produces behavioral evidence of neuropathic pain. In the present experiments we examined the involvement of capsaicin-sensitive afferents in mediating the thermal hyperalgesia produced by this model. Male Sprague-Dawley rats, treated as neonates (within 48 h of birth) with capsaicin (50 mg/kg, s.c.) or vehicle, were used at 16-18 weeks of age. Chromic gut sutures (4-0) were tied around the left sciatic nerve and withdrawal latencies of both hind paws to radiant heat were determined on postoperative days 3, 5, 10 and 20. Whereas there was a pronounced thermal hyperalgesia which lasted for up to 20 days in vehicle-treated rats, there was no evidence of thermal hyperalgesia in capsaicin-treated rats. There was no difference in baseline (pre-surgery) withdrawal latencies between the two groups. Radioimmunoassay revealed that there was a significant depletion of substance P (43.8%) and calcitonin-gene-related peptide (72.6%) in the lumbar spinal cord of neonatal capsaicin-treated rats compared to vehicle-treated rats. These results demonstrate that the chromic gut-induced thermal hyperalgesia is mediated by capsaicin-sensitive afferents and suggest that central mechanisms which process and control the reflex response to heat are different than mechanisms involved in thermal hyperalgesia.
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PMID:Neonatal capsaicin treatment prevents the development of the thermal hyperalgesia produced in a model of neuropathic pain in the rat. 128 62

Light and electronmicroscopic data reveal the presence of a well developed nerve plexus in the gut of the earthworm. The plexus contains subepithelial solitary nerve cells and fibers and an extensive neuropil among the muscle cells. There are two types of nerve cells in the enteric plexus. The first type contains mainly dense-core vesicles, and exhibits glyoxylic-acid induced fluorescence. Since none of these cells showed serotonin immunoreactivity, they are probably noradrenergic or dopaminergic. The second type contains large dense granules, suggesting that these cells are peptidergic (neurosecretory). A part of these cells are substance P immunoreactive, however no NPY, CGRP, or proctolin immunopositive cells were found. Ultrastructurally seven types of nerve fibers can be distinguished in the neuropil. Their distribution shows great variability within parts of the enteric canal. The observation that only two types of nerve cells are located within the gut makes it probable that some of the axons are extrinsic. According to immunohistological studies they may come from the stomatogastric system or from the segmental nerves. This is further supported by the fact that there is a well-developed subepithelial serotoninergic plexus in the fore-gut. Two types of neuromuscular junctions can be visualized in the muscular layer. The first type, representing a phylogenetically earlier form, exhibits wide junctional gap and pre- or postjunctional membrane thickening. The second type is the close contact. There are significantly more junctions observed in the fore-gut than in other parts of the gut.
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PMID:Immunohistochemical and ultrastructural study of the enteric nervous system of earthworm, Lumbricus terrestris L. 128 60

Some neurochemical changes in the gut of rats after five weeks of alloxan-induced diabetes were investigated. It was found that at this stage of diabetes the changes were restricted mainly to the small intestine with a special selectivity for the duodenum. No changes were found in the most part of the large intestine and rectum. The methionine-enkephalin content was markedly reduced throughout the small intestine, while vasoactive intestinal polypeptide was increased in duodenum, ileum and caecum. Substance P content was unaffected, while at later stages of the disease it was significantly reduced in the entire small intestine. Sympathetic noradrenaline and intrinsic serotonin contents were significantly increased in the duodenum and unchanged throughout the rest of the intestine. These data suggest that the small intestine and caecum might be the early target of diabetic autonomic neuropathy, that might involve progressively the rest of the large intestine at later stages as recent results have suggested. It is likely that the gastrointestinal dysfunctions, often present in diabetic patients, might also be due to the combined pre-synaptic alterations, and to the functional imbalance between Gs and Gi/Go transduction proteins recently reported. Insulin therapy, begun seven days after alloxan treatment, reduced drastically the hyperglycaemia, restored normal body growth and prevented all the gut neurochemical changes associated with alloxan-induced diabetes.
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PMID:Early neurochemical changes in the autonomic neuropathy of the gut in experimental diabetes. 128 97

Autonomic neuropathy and gastrointestinal problems are among the most common complications of diabetes. In this report it is shown that a possible correlation between the two disorders might exist, since diabetes causes a profound alteration of the peptidergic innervation of the gut. It is reported that 14 weeks after diabetes induction with alloxan the levels of substance P and methionine-enkephalin are markedly reduced throughout the intestine, while vasoactive intestinal polypeptide content is dramatically increased. Therefore the enteric innervation of diabetic animals is completely disorganized, with some systems undergoing atrophy and others undergoing hypertrophy. Treatment of diabetic animals with acetyl-L-carnitine prevents the onset of the marked peptide changes described above. The results suggest a potential for acetyl-L-carnitine in the treatment of autonomic neuropathies.
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PMID:Peptide alterations in autonomic diabetic neuropathy prevented by acetyl-L-carnitine. 128 98

Neurokinins (NK) are a group of peptides that share a common C-terminal and play an important role in control of the motor functions of the mammalian gut. Neurokinin receptors such as NK1, NK2 are certainly present in any segment of gut, whereas the NK3 receptors are probably present in the ileum of the Guinea pig and duodenum of the rat. We measured gastrointestinal responses with natural NK and their very specific agonists to determine the probable receptors in the stomach and small intestine of Sprague-Dawley rats. After overnight fasting, the rats were intubated with a catheter to feed saline liquid meal that contained 10% charcoal. Simultaneously, various doses of NK ranged selected from 10(-10) and 10(-7) mol kg-1 included substance P (SP), neurokinin A (NKA), neurokinin B (NKB), septide, [Nle10]-NKA4-10, senktide, and vehicle were intraperitoneally injected. At 15 min after being fed test meal, the rats were sacrificed. Then we removed entire gut including the stomach to measure the total length of small intestine and transit length of the charcoal, from which the transit ratio was calculated. In comparison with ratios of rats treated with vehicle, the inhibited transit ratios for charcoal were seen among SP at 10(-10) mol kg-1, NKA at 10(-10) and 10(-7) mol kg-1, [Nle10]-NKA4-10 at 10(-7) mol kg-1, and senktide at all doses except 10(-8) mol kg-1. Enhanced transit ratios were seen for septide at the doses 10(-8) and 10(-7) mol kg-1. Likewise the mean total intestinal lengths of rats if they received various treatments of peptides except that rats treated with NKB had somewhat diminished length than those of vehicle-treated rats. Some natural NK and their very specific receptor agonists mainly inhibited rat gastrointestinal charcoal transits. We suggest the probable presence of NK1, NK2 and NK3 receptors in the small intestine and stomach including pylorus of the rat.
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PMID:The motor actions of natural neurokinins and their specific agonists on the gastrointestinal tract of the rat. 128 5

In the present work it we describe serotonin, noradrenaline, proctolin, neuropeptide Y, substance P, and calcitonin gene related peptide immunoreactive structures in earthworm. A few large serotonin immunoreactive perikarya are located in brain and in the stomatogasric ganglia and many of them in the segmental ganglia. A serotonin immunoreactive fiber plexus can be seen beneath the epithelium of the body wall, both the sensory papillae and chaetae contain serotonin immunoreactive elements. Some of the sensory cells are serotonin immunoreactive, too. A serotonin immunoreactive network can ben found in the enteric network of the fore- and mid-gut. Only a few noradrenaline immunoreactive cells are observed in the caudal part of the brain, while their number in the segmental ganglia is high. Proctolin-, and substance P immunoreactive cells are small and numerous in the brain without any preference in their location. Such nerve cells are widely distributed in the ganglia of the stomatogastric system, in the subesophageal and in segmental ganglia. Many surface epithelial (probably sensory) cells are proctolin immunoreactive. Substance P immunoreactive nerve cells can also be located in the entire length of the enteric plexus together with substance P immunoreactive fibers. No neuropeptide Y- or calcitonin gene related peptide immunoreactive structures can be seen in the brain. A relative small number of neuropeptide Y- and calcitonin gene related peptide immunoreactive perikarya, and a rich network of neuropeptide Y- and calcitonin gene related peptide immunoreactive fibers can be detected in the subesophageal ganglion. According to preliminary studies, neuropeptide Y is probably co-localized with serotonin.
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PMID:Immunohistochemical study of the nervous system in earthworm (Lumbricus terrestris L.). 129 14


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