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)

The isolated, perfused gland was used to examine the regulation of saliva volume and protein content by vasoactive intestinal peptide (VIP). In the absence of other secretagogues, VIP produced a modest, sustained saliva flow with a biphasic dose-response curve in which saliva volume was greatest at 1 nM VIP (28.5 +/- 3.8 microliters in the first 5 min, n = 4) but reduced at lower and higher concentrations. The protein concentration in saliva released in response to VIP (0.86 +/- 0.13 micrograms/microliters) was substantially higher than with 30 nM acetylcholine (0.06 +/- 0.02 micrograms/microliters) or 1 nM substance P (0.30 +/- 0.05 micrograms/microliters). During the first 5 min of stimulation, VIP and substance P were synergistic in terms of volume and protein content whereas inclusion of VIP did not increase acetylcholine-stimulated flow in the first 5 min but produced a higher sustained flow over the next hour. After stimulation with acetylcholine, subsequent addition of VIP transiently enhanced saliva volume and protein content in a monophasic, dose-dependent manner with effects at 1 pM VIP and higher. The responses were different for VIP compared with other cAMP-mobilizing agents and the involvement of multiple VIP receptor subtypes was suggested from experiments in which a VIP antagonist blocked the VIP enhancement of saliva volume but not the increase in protein.
 ...
PMID:Regulation of secretion by vasoactive intestinal peptide in isolated perfused rat submandibular glands. 138 77

We studied the effect of vasoactive intestinal peptide (VIP), somatostatin (SOM), and substance P (SP) on IL-4-stimulated human IgE and IgG subclass production. VIP and SOM, but not SP, inhibited IgE production without affecting IgM or IgA production by mononuclear cells (MNC) from nonatopic donors from 10 pM to 10 nM. These neuropeptides also differentially modulated IgG subclass production. While IgG1 production was not affected by VIP, SOM, or SP, all of the neuropeptides enhanced IgG2 production. By contrast, SOM and SP, but not VIP, inhibited IgG3 production, whereas VIP and SP, but not SOM, enhanced IgG4 production. The effect by neuropeptides was specific since each peptide effect was specifically blocked by each antagonist. To achieve this effect, neuropeptides must be added at the start of the culture and be present throughout the entire culture period. The inhibition of IgE production was not mediated by known inhibitors of IgE production, IFN-gamma or PGE2, because the addition of anti-IFN-gamma mAb (10 micrograms/ml) or indomethacin (0.1 microM) did not overcome the inhibition of IgE production. In contrast to MNC, neuropeptides did not affect IgG subclass production in purified B cells. IgE production was not induced by IL-4 in purified B cells. Neuropeptides also failed to modulate IgG subclass production in cultures of B cells with either T cells or monocytes. However, they modulated IgE production and IgG subclass production in B cells in the presence of T cells and monocytes. In purified B cells, IL-4 plus anti-CD40 mAb induced IgE production which was not inhibited by VIP or SOM. However, VIP or SOM, but not SP, inhibited IgE production in B cells cultured with both T cells and monocytes. Finally, the mechanism of modulation of IgE and IgG4 production was dependent on IL-4-induced switching, since neuropeptides modulated IgG4 and IgE production in surface IgG4-negative (sIgG4-) and sIgE- B cells, respectively. In contrast, modulation of IgG2 and IgG3 production was not due to switching, since neuropeptides did not affect either IgG2 or IgG3 production in sIgG2- or sIgG3- B cells, respectively.
 ...
PMID:Differential effect of vasoactive intestinal peptide, somatostatin, and substance P on human IgE and IgG subclass production. 138 70

The local production of autocrine or paracrine agents in endocrine tissues represents an important level of hormonal regulation. The synthesis of neuropeptide-Y (NPY), substance-P (SP), and vasoactive intestinal peptide (VIP) in the rat anterior pituitary gland has been well demonstrated. We have now studied their expression in human postmortem pituitary tissue. Northern blot analysis of poly(A)+ RNA from whole human pituitaries revealed mRNA encoding the precursors for NPY, SP, and VIP whose hybridization characteristics were indistinguishable from those of the same mRNAs described in previously characterized human tissues. VIP mRNA was detectable in all samples tested, with NPY and preprotachykinin-A mRNA (which encodes SP) detectable in a subset of the pituitaries. The concentration of immunoreactive NPY in whole human pituitary was 3.8 +/- 1.1 pmol/g wet wt in males and 2.9 +/- 0.5 pmol/g wet wt in females (mean +/- SEM; n = 10), that of SP was 3.1 +/- 0.4 pmol/g wet wt in males and 5.2 +/- 1.3 pmol/g wet wt in females (n = 10), and that of VIP was 8.1 +/- 2.9 pmol/g wet wt in males and 5.3 +/- 1.6 pmol/g wet wt in females (n = 10). Size-fractionation of pituitary extracts by gel permeation chromatography revealed single peaks of NPY and VIP-like immunoreactivity in the positions of the standards, while SP-like immunoreactivity mostly eluted in the position of synthetic SP, with two minor immunoreactive peaks eluting earlier. The low levels of NPY, SP, and VIP and their mRNAs in the human pituitary are consistent with peptides having an autocrine/paracrine, rather than endocrine, mode of action.
 ...
PMID:Expression of messenger ribonucleic acids encoding neuropeptide-Y, substance-P, and vasoactive intestinal polypeptide in human pituitary. 138 56

Depolarization has been shown to alter the biosynthesis of a number of neurotransmitters and neuromodulators. In the rat superior cervical ganglion (SCG), for example, depolarization has been reported to increase catecholamine biosynthesis and to decrease the level of substance P. We have recently found that, although the level of vasoactive intestinal peptide (VIP)-like immunoreactivity (IR) is normally low in the SCG, it increases significantly 48 hr after adult ganglia are deafferented in situ or placed in organ culture. Both manipulations decrease electrical activity of postganglionic neurons. To determine whether the increases in ganglionic VIP-IR could be a consequence of decreased depolarization of sympathetic neurons, the effect of depolarization on the expression of VIP-IR was examined in organ cultures of neonatal and adult SCG. Depolarization with elevated K+ (30 mM) or veratridine (1.5 microM) amplified, rather than blocked, the increases in VIP-IR content seen after 24 hr. Further, it increased the number of detectable VIP-IR neuronal cell bodies and processes. The stimulatory effects of veratridine were prevented by TTX. Since similar changes in expression of VIP-IR were evident in dissociated cell cultures of the SCG, cell-cell interactions requiring intact ganglionic architecture are not necessary for altered peptide expression. Elevating the concentration of Mg2+ blocked the ability of K+ and veratridine to increase VIP-IR in dissociated cell culture, raising the possibility that the effects of depolarization on VIP-IR are mediated by increased Ca2+ entry. The depolarizing conditions that increased VIP-IR also increased substance P-IR. While higher concentrations of veratridine (50 microM) blocked the elevation of both VIP- and substance P-IR induced by explantation, they produced significant neuronal death. Since depolarization with either 30 mM KCl or 1.5 microM veratridine increases expression of VIP-IR in neonatal and adult ganglia, decreased depolarization is unlikely to cause the increases in VIP- and substance P-IR that occur in culture. Furthermore, our data raise the possibility that sympathetic nerve activity in vivo can increase expression of these peptides.
 ...
PMID:Depolarization increases vasoactive intestinal peptide- and substance P-like immunoreactivities in cultured neonatal and adult sympathetic neurons. 138 75

Acute inflammation of the colonic wall was induced by perendoscopic injection of formalin in rats. As compared to control animals (no endoscopy, no injection), the procedure was followed by a marked reduction of immunoreactive substance P, calcitonin gene-related peptide and vasoactive intestinal peptide concentrations in rectosigmoid wall. Tissue substance P concentration in the spinal cord, at the level of afferent projection, increased at the same time. The three peptides tested are thus likely to be involved in the pathophysiology of acute intestinal inflammation. In addition, substance P may play a role in the transmission of nociceptive signals from the inflamed colonic segment.
 ...
PMID:Spinal and intestinal levels of substance P, calcitonin gene-related peptide and vasoactive intestinal polypeptide following perendoscopic injection of formalin in rat colonic wall. 138 64

The hypothalamo-neurohypophyseal tract is known to contain the classical neurohypophyseal hormones vasopressin and oxytocin. Additionally, dynorphin, methionine- and leucine-enkephalin, cholecystokinin (CCK), corticotropin-releasing factor (CRF), and galanin are co-stored with vasopressin and/or oxytocin. Recent immunohistochemical studies have revealed the existence of a low to moderate number of substance P-, vasoactive intestinal peptide (VIP)-, neuropeptide Y (NPY)- and somatostatin-immunoreactive nerve fibers within the rat neurohypophysis. VIP-, substance P- and NPY-immunoreactive fibers were distributed throughout the organ, whereas somatostatin-immunoreactive fibers were present in the proximal part of the organ. The positive nerve endings were either large in size resembling classical nerve terminals related to perivascular spaces, or smaller similar to peptidergic fibers as described in the CNS. These results indicate that these neuropeptides may be either co-stored with the classical neurohypophyseal hormones or contained in another system of afferents to the organ. The probably distinct functional roles of these neuropeptides in the physiology of the neurohypophysis are discussed.
 ...
PMID:Non-vasopressinergic, non-oxytocinergic neuropeptides in the rat hypothalamo-neurohypophyseal tract: experimental immunohistochemical studies. 138 83

We investigated the possibility of nitric oxide (NO), a powerful vasodilator agent, being synthesized by perivascular nerve fibres. Immunoreactivity and catalytic activity of the NO synthesizing enzyme, NO synthase (NOS), were demonstrated in perivascular nerve fibres of blood vessels receiving autonomic vasodilator innervation, but not of those innervated exclusively by vasoconstrictor nerve fibres. Double-labelling techniques allowed identification of NOS-containing nerve fibres as belonging to the vasoactive intestinal peptide (VIP)/acetylcholine-containing class whereas noradrenergic and substance P-containing perivascular fibres were devoid of NOS. We suggest that, in addition to its endothelial source, NO is a neuronal co-mediator of VIP/cholinergic vasodilation.
 ...
PMID:Nitric oxide synthase in VIP-containing vasodilator nerve fibres in the guinea-pig. 138 69

The present work was undertaken to determine by immunocytochemical methods which of the putative enteric neurotransmitters are contained in axons supplying the guinea-pig taenia coli and what proportion of axons is accounted for by the presence of these substances. Numerous fibres displayed immunoreactivity for dynorphin (DYN), enkephalin (ENK), gamma-aminobutyric acid (GABA), nitric oxide synthase (NOS), substance P (SP) and vasoactive intestinal peptide (VIP), but, in contrast to other gut regions, fibres showing immunoreactivity for gastrin-releasing peptide, galanin and neuropeptide Y were rare in the taenia. Fibres reactive for calbindin, calcitonin gene-related peptide, cholecystokinin, 5-hydroxytryptamine and somatostatin were also rare. Tyrosine hydroxylase-like immunoreactivity (TH-LI) was present in numerous fibres that disappeared after extrinsic denervation, a procedure that did not detectably affect any of the other major groups of fibres. Simultaneous staining of extrinsically denervated preparations revealed that SP-LI and VIP-LI were located in separate fibres, and ultrastructural studies showed these to be 58% and 33% of intrinsic fibres supplying the muscle. Immunoreactivity for the general marker, neuron-specific enolase, was located in 95-98% of axons. ENK-LI and DYN-LI were in the same axons, and similar proportions of the fibres with either SP-LI or VIP-LI, about 85%, contained immunoreactivity for ENK and DYN. All VIP-LI fibres, but no SP-LI fibres, were reactive for NOS. The results imply that the taenia of the guinea-pig caecum is innervated by two major groups of enteric neurons: (i) excitatory neurons that contain ACh, SP, other tachykinins, and, in most cases, DYN-LI and ENK-LI; and (ii) inhibitory neurons that contain NOS-LI, VIP-LI, in most cases, the two opioids and, quite probably, ATP as a transmitter. GABA-LI is contained in a smaller population of intrinsic axons. Even though the taenia represents one of the simplest tissues for examining transmission from enteric neurons to intestinal muscle, it shares some of the complexity of other regions, in that four major axon types supply the muscle and both the enteric excitatory and enteric inhibitory neurons contain multiple transmitters.
 ...
PMID:Light- and electron-microscopic immunochemical analysis of nerve fibre types innervating the taenia of the guinea-pig caecum. 138 81

The effect of neuropeptide Y (NPY) was tested on isolated guinea pig trachea. At 30 nM, NPY induced a weak but significant contractile response which was on average less than 6% of responses elicited by standard spasmogens. This myotropic action of NPY was blocked by indomethacin. In addition to its contractile activity, NPY greatly reduced the maximal response to vasoactive intestinal peptide (VIP), noradrenaline (NA), substance P (SP) and 5-hydroxytryptamine (5-HT), without affecting their pD2 values. However, NPY did not influence the response induced by histamine and carbamylcholine. Pretreatment of tracheal spirals with indomethacin (10(-6) M) abolished the NPY-evoked inhibition of VIP, SP and 5-HT responses but failed to reduce the action of NPY on NA-elicited relaxation. This latter effect was however blocked in the presence of tetrodotoxin. In conclusion, NPY inhibits responses elicited by various agonists in the guinea pig trachea. This effect seems to be mediated at both pre- and postjunctional levels. The postjunctionally mediated inhibitory action of NPY appears to be expressed especially with agents that generate prostaglandins concomitantly with inducing their response. In contrast, the NPY-evoked inhibition of NA-evoked relaxation seems to be mediated via a prejunctional mechanism.
 ...
PMID:Inhibitory action of neuropeptide Y on agonist-induced responses in isolated guinea pig trachea. 138 64

To investigate synaptic mechanisms in taste buds and collect information about synaptic transmission in these sensory organs, we have examined taste buds of the mudpuppy, Necturus maculosus for the presence of neurotransmitters and neuromodulators. Immunocytochemical staining at the light microscopic level revealed the presence of serotonin-like and cholecystokinin-like (CCK) immunoreactivity in basal cells in the taste bud. Nerve fibers innervating taste buds were immunoreactive for vasoactive intestinal peptide-like (VIP), substance P-like, and calcitonin gene-related peptide-like (CGRP) or compounds closely related to these substances. Immunoreactivity for tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) in the taste cells and nerve fibers was absent. These data suggest that serotonin, CCK, VIP, substance P, and CGRP are involved in synaptic transmission or neuromodulation in the peripheral organs of taste. No evidence was found for cholinergic or adrenergic mechanisms on the basis of the absence of immunocytochemical staining for key enzymes involved in these two transmitter systems.
 ...
PMID:Immunocytochemical survey of putative neurotransmitters in taste buds from Necturus maculosus. 138 95


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>