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)

Using the sucrose gap method, the effect of taurine on the spinal cord of the bullfrog was investigated. Taurine inhibited the spontaneous potential and the ventral root reflex potential elicited by the stimulation of the dorsal root. The excitability of motoneuron did not necessarily diminish following taurine application. Taurine inhibited the responses induced by excitatory neurotransmitter candidates such as, glutamate and substance P, in a concentration dependent manner in the preparation, where the neurotransmission was abolished by Ca2+-deprivation and/or Mg2+-supplement. From these results, the depressant action of taurine on the electrical activities in the frog spinal cord may be interpreted, in part, by the inhibition of the response evoked by excitatory transmitter at postsynaptic site.
 ...
PMID:Inhibitory action of taurine on motoneuron of frog spinal cord. 241 93

The most important central autonomic pathways in the control of arterial blood pressure are the baroreceptor reflex pathway and descending pathways from the hypothalamus. Central neurotransmitters in these pathways are L-glutamate, substance P, norepinephrine (NE), gamma-aminobutyric acid, epinephrine, neuropeptide Y, and acetylcholine. At peripheral autonomic neurovascular junctions, there are prejunctional alpha 2- and dopamine-2 receptors, which inhibit NE release, and beta- and serotonin receptors, which stimulate NE release. Postjunctional alpha 1-receptors open sodium channels, open calcium channels via phosphoinositol release, and release intracytoplasmic calcium. Postjunctional alpha 2-receptors, which are extrasynaptic, inhibit adenylate cyclase and also open calcium channels. In animal models of hypertension, changes in alpha-receptor density have been reported. In spontaneously hypertensive rats, increased renal beta- and alpha 2-receptors, respectively, may enhance renin release and cause sodium and water retention. In experimental (renovascular) hypertension, vascular postsynaptic (vasoconstrictor) alpha 1- and alpha 2-receptors are increased. In both models of hypertension, beta-receptors are down-regulated. Selective alpha 1-antagonists, such as indoramin and prazosin, decrease arterial blood pressure by postsynaptic alpha 1-blockade; alpha 2-receptor inhibition of NE release is unaffected so that there is no beta-receptor-mediated tachycardia.
 ...
PMID:Alpha-adrenoreceptors in hypertension. 242 93

A comparison has been made between the effects of intrathecally administered L-glutamate, L-aspartate, substance P and calcitonin gene-related peptide (CGRP) on the excitability of rat flexor alpha-motoneurons activated monosynaptically by Ia afferents and polysynaptically by high mechano-threshold cutaneous afferents. At doses that do not modify the monosynaptic reflex, substance P, CGRP and some factor released from sural C-fibres increase the excitability of the nociceptive flexion reflex for prolonged periods in a multiplicative fashion. The excitatory amino acids have no such action. We suggest that one role for C-afferent neuropeptides is a long-acting gain modulation of nociceptive inputs into the spinal cord.
 ...
PMID:Substance P and calcitonin gene-related peptide synergistically modulate the gain of the nociceptive flexor withdrawal reflex in the rat. 242 87

We have developed a dissociated primary cell culture of noradrenergic neurons from the locus ceruleus of postnatal (1- to 5-d-old) mice or rats. Slices of the brain stem were made on a Vibratome. Then the region of locus ceruleus, which was identified by observing the slices under a dissecting microscope, was dissected out from the slices. The removed fragments of brain slices were dissociated and cultured up to 3 weeks on a non-neuronal feeder layer, which consisted predominantly of astroglial cells, or on a fibronectin-treated collagen substratum. After 2 weeks of culture, about 70% of total neuronlike cells revealed positive catecholamine histofluorescence, indicating that they were probably noradrenergic neurons. About 98% of large- and medium-sized cultured neurons (soma diameter greater than or equal to 20 microns) was histofluorescence positive. The fluorescence-positive cells had long processes rich in varicosities, and the shape of their soma was either multipolar or fusiform. Electron microscopy using permanganate fixation revealed that the varicosities along their processes had small granular vesicles, which may contain norepinephrine. Physiological properties of these noradrenergic neurons were investigated with intracellular microelectrodes or with the whole-cell version of the patch clamp. We observed that many cells were producing spontaneous firing. Many of these spontaneously firing cells had no obvious contact with neighboring cells. The neurons were depolarized when glutamate was applied by pressure ejection. They also responded to GABA and glycine with either hyperpolarization or depolarization, and these responses were antagonized by picrotoxin and strychnine. Application of substance P generally produced depolarization with an increase in input resistance. The neurons responded with hyperpolarization to somatostatin, beta-endorphin, and enkephalin. This culture system will become a useful tool for elucidating the cellular and molecular properties of the central noradrenergic neurons.
 ...
PMID:Noradrenergic neurons from the locus ceruleus in dissociated cell culture: culture methods, morphology, and electrophysiology. 243 74

We have sought to determine if changes in arterial and gastric pressure occurred with selective chemical stimulation of the dorsomedial NTS. Substance P (SP) and L-glutamate (L-glu), but not acetylcholine (ACh), elicited a dose-dependent decrease in tonic gastric pressure and inhibited gastric phasic activity. As previously reported, L-glu and ACh, but not SP elicited dose-dependent arterial hypotension. The data support a putative role for SP in visceral reflexes mediated by vagal nerves.
 ...
PMID:Central modulation of gastric pressure by substance P: a comparison with glutamate and acetylcholine. 243 Jun 70

The effect of D-Arg1, D-Trp7,9, Leu11-substance P (SP) (spantide), a putative SP antagonist, on SP-induced facilitation of the flexion reflex was examined. The drugs were injected intrathecally (i.t.) in decerebrate, spinalized, unanaesthetized rats. Substance P (10 ng) caused an increase in reflex magnitude for about 5 min. Spantide (10 ng and 100 ng) also caused a facilitation of the reflex that was similar to SP. Spantide (10 ng) plus SP (10 ng) also had a similar excitatory effect. One microgram of spantide totally blocked the flexion reflex, which could not be reversed by SP, L-glutamate, L-aspartate or naloxone. It is concluded that spantide does not have an antagonistic effect on SP-induced changes in spinal reflex excitability. Some of the effects of i.t. spantide observed in behavioural studies may be due to a non-specific spinal motor block. It is suggested that the flexion reflex in the decerebrate, spinalized rat is a useful physiological model in studies of the effects of algesic and analgesic drugs at spinal level.
 ...
PMID:D-Arg1, D-Trp7,9, Leu11-substance P (spantide) does not antagonize substance P-induced hyperexcitability of the nociceptive flexion withdrawal reflex in the rat. 243 39

In anaesthetised rats recordings were made of sympathetic activity in renal nerves whilst studying the effects of intrathecal injection of the substance P antagonist (D-Arg1, D-Pro2, D-Trp7,9, Leu11)-substance P on the responses to, stimulation of the ventrolateral medulla, to intrathecal injection of substance P, serotonin and glutamate. All responses were abolished by the antagonist.
 ...
PMID:The action of a substance P antagonist on sympathetic nerve activity in the rat. 243 97

Regional central nervous system and peripheral hemodynamic effects of the intrathecal (i.t.) administration of a substance P (SP) receptor antagonist, [D-Arg1, D-Pro2, D-Trp7,9, Leu11]-substance P ([D-Arg]-SP), were studied in anesthetized rats. It was found that [D-Arg]-SP (3.3 nmol i.t.) reduced mean arterial pressure and cardiac output due to a reduction in stroke volume. Total peripheral resistance was not altered. Whereas most vascular beds showed no alterations in vascular resistance, a renal vasoconstriction was noted. The hypotensive effect of [D-Arg]-SP was blocked by phentolamine (10 mg/kg i.v.) but not by propranolol (1 mg/kg i.v.). In the absence of changes in vascular arterial resistance due to [D-Arg]-SP, it appears that a change in venous return may contribute to the [D-Arg]-SP-induced reduction in stroke volume. These data provide evidence that a spinal cord SP system may tonically affect sympathetic neurons controlling venous, but not arterial, vasomotor tone. [D-Arg]-SP (i.t.) did not alter brain blood flow but significantly decreased blood flow in the thoracolumbar spinal cord 15 to 20 min after administration. The reduction in spinal cord flow did not appear to be responsible for the [D-Arg]-SP-induced hypotension because kainic acid (i.t.), an agent that interacts with glutamate receptors, produced similar pressor responses in the presence and absence of [D-Arg]-SP. In addition, whereas the pressor effect of low doses of a SP agonist [pGlu5, MePhe8, MeGly9]-substance P (5-11) were blocked by [D-Arg]-SP, a higher dose produced the typical pressor effect.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Intrathecal administration of a substance P receptor antagonist: studies on peripheral and central nervous system hemodynamics and on specificity of action. 244 Oct 24

We investigated quantitative changes in markers of possible neurotransmitters in the dorsal column nuclei following transection of the dorsal column in the cat. Seven days after unilateral transection of the dorsal column at the upper cervical level, choline acetyltransferase activity and concentrations of glutamate, aspartate, gamma-aminobutyrate and substance P were measured throughout the longitudinal axis of the dorsal column nuclei. In addition, high-affinity uptake of choline, D-aspartate and gamma-aminobutyrate into the synaptosomal fraction of the dorsal column nuclei were also measured. Choline acetyltransferase activity and high-affinity choline uptake were reduced by approx. 30% on the caudal to the obex. Reduction of high-affinity uptake of D-aspartate by approx. 30% was observed on the operated side in the central part of these nuclei, although the decrease in glutamate and aspartate was not significant in the nuclei on the operated side compared with that on the intact side. No significant changes were found in the high-affinity uptake of gamma-aminobutyrate or the contents of gamma-aminobutyrate and substance P in any areas of the dorsal column nuclei. These results suggest that not only glutamate and/or aspartate but also acetylcholine may be neurotransmitter candidates for the ascending fibres terminating in the dorsal column nuclei, whereas there may be few fibres containing substance P or gamma-aminobutyrate in the dorsal column.
 ...
PMID:Possible neurotransmitters of the dorsal column afferents: effects of dorsal column transection in the cat. 244 4

The neurokinins, physalaemin, substance P, neurokinin A and bradykinin, were tested on the responses of single spinal neurons to the purines, adenosine 5'-triphosphate (ATP) and adenosine 5'-monophosphate and to GABA. Experiments were done on anaesthetized cats, recording extracellularly from functionally identified sensory neurons in the lumbar dorsal horn. All compounds were administered by iontophoresis. Neurokinins caused a slow, prolonged excitation which outlasted the period of application. Physalaemin was tested on responses to ATP in 24 units. In each case application of ATP caused either depression, excitation or a biphasic response when the application was not pre-conditioned by ejection of physalaemin. For 11 units, with ATP applications subthreshold to alter the on-going firing rate, such applications caused depression when they were preceded by administration of physalaemin. Three units were tested with ATP applications which caused the excitatory response; when the applications of ATP were preceded by ejection of physalaemin, there was then a depressant component in the response. In these 14 cases, the magnitude of the depression or of the depressant component of the response, was measured using currents which failed to produce depression in the absence of physalaemin ejection; the mean magnitude of this depression was 34.7 +/- 1.6% (+/- S.E.M.). With the 10 remaining units, responses to ATP were unaffected by application of physalaemin. The early components of the biphasic and excitatory responses were unaffected by physalaemin and hence it appeared to have a differential effect, enhancing only the depressant effects of ATP. The enhancement of depression was reversible, lasting up to 30 min following a single ejection. Neither control current nor glutamate mimicked the effect of physalaemin in the responses to application of ATP. The depressant response to adenosine 5'-monophosphate was also enhanced by physalaemin: ejections of adenosine 5'-monophosphate subthreshold to affect the on-going firing rate caused depression after physalaemin application in 3 of 8 units (average depression: 35.0 +/- 3.3%). On the other hand, depression induced by GABA was unaffected by physalaemin in every case (n = 8); in 4 of these cases GABA was tested on units for which purine-induced depression was enhanced by physalaemin. Thus, physalaemin preferentially affected depressant responses to ATP and to adenosine 5'-monophosphate.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Purine-induced depression of dorsal horn neurons in the cat spinal cord: enhancement by tachykinins. 244 38


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