Search results for "Tachykinin receptor"
showing 7 items of 7 documents
Tachykinin NK(2) receptors facilitate acetylcholine release from guinea-pig isolated trachea.
2000
The release of newly synthesised [3H]acetylcholine was evoked by electrical field stimulation (5 Hz, 600 pulses) of epithelium-deprived guinea-pig trachea strips after sensory neuropeptides depletion with 3 microM capsaicin. The selective tachykinin NK(2) receptor agonist [betaAla(8)]neurokinin A-(4-10) increased in a concentration-dependent manner the electrically-induced release of [3H]acetylcholine. The facilitatory effect was antagonised by the selective non-peptide tachykinin NK(2) receptor antagonist, SR 48968 (apparent pK(B) 8.9). The tachykinin NK(1) and NK(3) receptor agonists substance P methyl ester and senktide (both 10 and 100 nM), respectively, did not affect the evoked releas…
Antagonist discrimination between subtypes of tachykinin receptors in the guinea-pig ileum.
1986
1. The effects of substance P and eledoisin on spontaneous and electrically-evoked release of [3H]acetylcholine, and on smooth muscle were studied in the guineapig myenteric plexus-longitudinal muscle preparation preloaded with [3H]choline. Substance P and eledoisin caused transient increases in spontaneous release of [3H]acetylcholine and in longitudinal muscle tone. Both tachykinins were equipotent in contracting the muscle, but eledoisin was more potent than substance P in eliciting [3H]acetylcholine release. The release caused by substance P was enhanced in the presence of naloxone and scopolamine which suggests that the release is modulated through opioid and muscarinic receptors. 2. S…
Differential effects of anandamide on acetylcholine release in the guinea-pig ileum mediated via vanilloid and non-CB1 cannabinoid receptors
2001
The effects of anandamide on [3H]-acetylcholine release and muscle contraction were studied on the myenteric plexus-longitudinal muscle preparation of the guinea-pig ileum preincubated with [3H]-choline. Anandamide increased both basal [3H]-acetylcholine release (pEC50 6.3) and muscle tone (pEC50 6.3). The concentration-response curves for anandamide were shifted to the right by 1 μM capsazepine (pKB 7.5 and 7.6), and by the combined blockade of NK1 and NK3 tachykinin receptors with the antagonists CP99994 plus SR142801 (each 0.1 μM). The CB1 and CB2 receptor antagonists, SR141716A (1 μM) and SR144528 (30 nM), did not modify the facilitatory effects of anandamide. Anandamide inhibited the e…
Characterization of tachykinin receptors in the uterus of the oestrogen-primed rat
1998
The aim of our study was to characterize the tachykinin receptor population in the oestrogen-primed rat uterus. For this purpose, we investigated the receptor type(s) responsible for tachykinin-induced contraction of longitudinally-arranged smooth muscle layer. The effects of substance P (SP), neurokinin A (NKA), neurokinin B (NKB) and several of their analogues with well-defined selectivities for tachykinin NK1, NK2 and NK3 receptors were studied and their inhibition by the selective nonpeptide tachykinin receptor antagonists (S)1-(2-[3-(3,4-dichlorophenyl)-1-(3-isopropoxyphenylacetyl)piperidin-3-yl]ethyl)-4-phenyl-1-azoniabicyclo[2.2.2]octane chloride (SR 140333, NK1-selective), (S)-N-met…
Peptidergic Innervation in Chronic Pancreatitis
1990
The reason for the generation and continuation of chronic pain in chronic pancreatitis is unclear [6, 10, 11, 13, 61, 117]. Current concepts of the neurobiology of pain point to the possible role of various neuropeptides in pain processing and inflammation [8, 29, 32, 33, 44, 60, 64, 65, 68, 79, 104, 112]. A key function has been ascribed to the proinflammatory and pronociceptive peptides of the tachykininin (TK) family (8, 44, 104, 109]. That the tachykinin substance P (SP) may be involved in chronic inflammatory and painful disease of the gastrointestinal system is evidenced by a selective increase in the density of tachykinin receptors in the bowels of patients suffering from Crohn’s dis…
Changes in the Expression of Tachykinin Receptors in the Rat Uterus During the Course of Pregnancy1
2001
In the mammalian female reproductive tract, tachykinin neuropeptides, such as substance P (SP), are localized to a population of sensory fibers and their precise physiological role is still unknown. The aim of the present study was to characterize the population of tachykinin receptors in the pregnant rat uterus and to assess their regulation during the course of pregnancy and after delivery. The expression of the tachykinin NK(1) receptor (NK(1)R), the tachykinin NK(2) receptor (NK(2)R), and the tachykinin NK(3) receptor (NK(3)R) in uteri from rats at different stages of pregnancy and on Day 1 postpartum was investigated by using a semiquantitative reverse transcription-polymerase chain re…
FUNCTIONAL STUDY ON THE ROLE OF TACHYKININS IN COLONIC PERISTALTIC ACTIVITY IN MICE
2009
Because the role of tachykinin receptors in colonic peristalsis remains incompletely understood, we studied the effect of tachykinin receptor antagonists on mouse colonic peristaltic activity. Peristaltic activity was assessed by quantifying the amplitude and interval of distension-induced pressure waves in proximal and distal colon segments of mice using a modified Trendelenburg set-up. We studied the effect of the NK1, NK2 and NK3 tachykinin receptor antagonists RP67580 (2 mM), nepadutant (1 mM) and SR142801 (0.3 mM) respectively. Gradual distension of proximal and distal colon segments induced repetitive rhythmic pressure waves which were blocked by tetrodotoxin (1 mM) and virtually abol…