Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P46098 (5-HT3 receptor)
 2,290 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In rabbits fed with hypercholesterolemic diet the normal coronary vasodilator response to serotonin is replaced by vasoconstriction sensitive to 5HT2 receptor blockade. These experiments were designed to determine the receptor subtype involved in the contractile response of large isolated coronary arteries (without endothelium) taken from control and atherosclerotic rabbits. In both tissues the agonists' rank potency was 5-carboxamidotryptamine > serotonin (5HT) > sumatriptan > 8-OHDPAT: (+/-)-8-Hydroxydipropylaminotetralin HBr > 2-methylserotonin. In arteries from young rabbits, 5HT and sumatriptan induced contractions which were not influenced by ketanserin up to 3 x 10(-8) M. However, the 5HT2 antagonist at the concentration of 10(-6) M induced a significant rightward shift of the concentration-response curves. The contractions to the two serotoninergic agonists were competitively inhibited by methiothepin. NAN 190, a 5HT1A antagonist, LY 53857, a 5HT1C and 5HT2 antagonist, cyanopindolol, a 5HT1A and 5HT1B antagonist and ICS 205-930, a 5HT3 and 5HT4 antagonist (up to 10(-6) M) did not inhibit the contractile response to 5HT. Rauwolscine (10(-6) M) significantly shifted the concentration-response curves to the two agonists. Very similar results were obtained in coronary arteries from atherosclerotic rabbits. These data demonstrate that in rabbit epicardial coronary artery smooth muscle, the receptor involved in the serotoninergic response is a 5HT1-like subtype, possibly a 5HT1D. In this preparation, under our experimental conditions, there was no evidence for the presence of 5HT2 receptors. The induction of atherosclerosis did not induce significant changes in the serotoninergic response in these large coronary arteries, illustrating the marked heterogeneity between microvasculature and large arteries in the rabbit heart.
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PMID:Serotoninergic receptor subtype in coronary artery smooth muscle from young and atherosclerotic rabbit. 830 47

This experiment was conducted to determine whether drugs acting on brain serotonin modulate the effects of the mu opioid, morphine, as measured by the squirrel monkey shock titration procedure and, if so, whether serotonergic modulation is mediated via specific 5HT receptor subtypes. Under this procedure, electric shock was delivered to the monkey's tail and scheduled to increase once every 15 s from 0.01 to 2.0 mA in 30 steps. Five responses on a lever during the 15-s shock period terminated the shock for 15 s, after which the shock resumed at the next lower intensity. The intensity below which monkeys maintained shock 50% of the time (median shock level or MSL) and rate of responding (RR) in the presence of shock were determined under control conditions and after administration of morphine alone and in combination with various serotonergic compounds. Morphine increased median shock level and decreased rate of responding in a dose-dependent manner. These effects of morphine was attenuated by the 5HT1A receptor agonists, 8-OH-DPAT [(+)-8-hydroxy-2(di-n-propylamino tetralin HBr] and ipsapirone. The effects of morphine were not altered by the 5HT1A receptor antagonist, NAN-190 [1-(2-methoxyphenyl-4-[4-(2-phthalimido) butyl] piperazine HBr], and 5HT2 receptor antagonist, ketanserin, the 5HT3 receptor antagonist, MDL 72222 [3-tropanyl-3,5-dichlorobenzoate], the alpha 2 adrenergic antagonist, yohimbine, or the alpha2 adrenergic agonist, clonidine. These results suggest that 5HT1A receptors may be involved in the effects of morphine in the shock titration procedure, whereas 5HT2, 5HT3 and alpha 2 adrenergic receptors do not appear to play a role in morphine's effects in this procedure.
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PMID:The role of serotonergic receptors in the effects of mu opioids in squirrel monkeys responding under a titration procedure. 885 15

The effects of ionophoretically applied 5-hydroxytryptamine (5-HT) and 5-HT receptor agonists were studied on rat nucleus tractus solitarius (NTS) neurones receiving unmyelinated vagal afferent input. 5-HT excited 15 of 34 neurones (44%), inhibited 10 (29%) and had no effect on nine. 8-Hydroxy-2-(di-N-propylamino)tetralin HBr (8-OH-DPAT) excited 23 of 53 neurones (43%), inhibited 24 (45%) and had no effect on six neurones and (+/-)-2,5-dimethoxy-4-iodoamphetamine HCl activated 18 of 37 neurones (49%), inhibited nine (24%) and had no effect on 10. These results demonstrate that activation of 5-HT1A and 5-HT2 receptors can excite or inhibit populations of NTS neurones. Phenylbiguanide, however, excited 20 of 23 neurones (87%), inhibited only one (4%) and had no effect on two indicating that 5-HT3 receptor activation has an excitatory action. NTS neurones receiving cardiac vagal afferent input were more likely to be excited by 5-HT (five of five, 100%) or 8-OH-DPAT (four of five. 80%) than the population as a whole. In conclusion, the data demonstrate that 5-HT1A, 5-HT2, and 5-HT3 receptor subtypes are functionally present on NTS neurones receiving excitatory vagal afferent input. Further, the subpopulation of NTS neurones receiving input from cardiac afferents are excited by 5-HT, possibly by an action on 5-HT1A or 5-HT3 receptors.
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PMID:In vivo effects of 5-hydroxytryptamine receptor activation on rat nucleus tractus solitarius neurones excited by vagal C-fibre afferents. 922 74

Ligands with varying intrinsic activity and selectivity for the various subtypes of the serotonin receptor were tested in the rat pup ultrasonic vocalization (USV) model, a putative animal model reflecting anxiety. USV were elicited by isolating rat pups from their mother and littermates by placing them on a warm (37 degrees C) or a cold (18 degrees C) plate. Concurrently, the negative geotaxic (NG) response and rectal temperature were determined to assess the potentially sedative and hypothermic effects of putative anxiolytics. USV were reduced at low doses and in both temperature conditions by the full 5-HT1A receptor agonists flesinoxan and 8-OH-DPAT (8-hydroxy-2-(di-n-propylamino) tetralin.HBr) and the partial 5-HT1A receptor agonists buspirone, ipsapirone and BMY 7378 (2-[4-[4-[2-pyrimidinyl]-1,2-piperazinyl]butyl]-1,2-benzi-isoth iozol-3-(2H)one-1,1-dioxide. 2HCl). The 5-HT1A receptor antagonists NAN-190 (1-(2-methoxyphenyl)-4-[4-(2-phtalimido)-butyl]piperazide.2H Cl), (+/-)-WAY 100,135 (+/-)-(N-tert-butyl-3(4-(2-methoxy phenyl)piperazin-1 -yl)-2-phenyl propionamine.2HCl), and ((S)-UH-301 (S)-5-fluoro-8-hydroxy-2-(di-n-propyl-amino)tetralin.HBr) reduced USV at higher doses and only in one of both test conditions. The selective 5-HT1A receptor antagonist DU 125530 (2-[4-[4[(7-chloro-2,3dihydro-4-benzodioxin-5-yl)-1-piperazi nyl]butyl]-1,2-benzisothiazol-3(2H)-one-1,1, dioxide, monomesylate), did not influence USV at the cold plate up to high doses, although concomitantly the negative geotaxis was disturbed. The negative geotaxis was impaired after all 5-HT1A receptor ligands, except BMY 7378 and (+/-)-WAY 100,135. Hypothermia coincided with USV-suppression, except for NAN-190 and (S)-UH-301. The USV-suppressing action of flesinoxan (3 mg/kg) could be antagonized by DU 125530, but not its NG effect. However, the hypothermia induced by flesinoxan was antagonized by DU 125530. USV were also suppressed by the 5-HT uptake inhibitors fluvoxamine (both warm and cold plate) and clomipramine (only warm plate). The tricyclic antidepressant imipramine only decreased USV on the cold plate, however, in a U-shaped dose-response curve. At the highest dose tested, no decrease was present. The 5-HT uptake stimulant tianeptine reduced USV under both conditions. Fluvoxamine had no side effects, clomipramine induced hypothermia and tianeptine clearly had sedative properties. The 5-HT1B/2C receptor agonist TFMPP (trifluorometaphenylpiperazine) stimulated USV at a low dose at the cold plate and suppressed USV at a high dose under both conditions. The 5-HT2A/2C receptor antagonist ketanserine enhanced USV at low doses under both conditions and had no effect at a higher dose. Concurrently heavy sedation and hypothermia occurred. The 5-HT3 receptor agonist phenylbiguanide and the 5-HT3 receptor antagonist ondansetron had no effect in this paradigm. Clearly, subtypes of the 5-HT receptor affect rat pup USV differentially.
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PMID:Ultrasonic vocalizations in rat pups: effects of serotonergic ligands. 988 14