5-HT inhibits spontaneous contractility of isolated sheep mesenteric lymphatics via activation of 5-HT(4) receptors.
N G McHale, K D Thornbury, M A Hollywood
文献索引:Microvasc. Res. 60(3) , 261-8, (2000)
全文:HTML全文
摘要
Spontaneous isometric contractions were measured in rings of sheep mesenteric lymphatic vessels in vitro. 5-Hydroxytryptamine (5-HT) produced a concentration-dependent decrease in spontaneous contraction frequency and force which was not antagonised by either the nonspecific 5-HT(1)/5-HT(2) receptor antagonist methysergide (1 microM) or the 5-HT(3) receptor antagonist ondansetron (1 microM). The 5-HT(4) receptor agonist BIMU-8 mimicked the inhibitory effect of 5-HT and its effects were abolished by the 5-HT(4) receptor antagonist DAU 6285 (1 microM). DAU-6285 also abolished the inhibitory effect of 5-HT and unmasked a weak excitatory response, which was mimicked by the 5-HT(2) receptor agonist alpha-methyl-5-hydroxytryptamine maleate. This excitatory response was, in turn, blocked by the 5-HT(2) receptor antagonist pirenperone (1 microM). The results of this study suggest that sheep mesenteric lymphatics possess both 5-HT(4) receptors and 5-HT(2) receptors. The inhibitory 5-HT(4) receptor appeared to be the predominant subtype since the excitatory response to 5-HT could only be observed in the presence of the 5-HT(4) receptor antagonist DAU 6285.Copyright 2000 Academic Press.
相关化合物
相关文献:
1994-03-01
[Pharmacol. Biochem. Behav. 47(3) , 575-8, (1994)]
1991-08-01
[Pharmacol. Biochem. Behav. 39(4) , 991-6, (1991)]
1999-03-01
[Pharmacol. Biochem. Behav. 62(3) , 543-7, (1999)]
1988-02-01
[Neuropharmacology 27(2) , 123-7, (1988)]
1987-01-01
[Gen. Pharmacol. 18(3) , 225-7, (1987)]