5-HT1-like and 5-HT2A receptors mediate 5-hydroxytryptamine-induced contraction of rabbit isolated mesenteric artery
Naunyn-Schmiedeberg's Archives of Pharmacology, cilt.352, sa.2, ss.127-131, 1995 (Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 352 Sayı: 2
- Basım Tarihi: 1995
- Doi Numarası: 10.1007/bf00176765
- Dergi Adı: Naunyn-Schmiedeberg's Archives of Pharmacology
- Derginin Tarandığı İndeksler: Scopus
- Sayfa Sayıları: ss.127-131
- Anahtar Kelimeler: 5-HT2A receptors, 5-Hydroxytryptamine, Rabbit mesenteric artery, Sumatriptan 5-HT1-like receptors
- Sağlık Bilimleri Üniversitesi Adresli: Evet
Özet
The contractions induced by 5-hydroxytryptamine (5-HT) and the 5-HT1-like receptor agonist, sumatriptan, were investigated in the open ring preparations of rabbit mesenteric artery in order to characterize the 5-HT receptors. 5-HT induced concentration-dependent contractions. Sumatriptan did not induce any contraction of unstimulated rings, whereas it elicited concentration-dependent contractions in preparations given a moderate tone by a threshold concentration of prostaglandin F2α (PGF2α). Pargyline, cocaine or normetanephrine were without significant effect on the contractions induced by 5-HT and sumatripan. The 5-HT concentration-effect curve was clearly biphasic. Methiothepin (0.01 μM) shifted the both phases of the concentration-effect curve to the right. Ketanserin (0.1 μM) shifted the second, low affinity, phase and prazosin did not alter concentration-effect curve to 5-HT. The sumatriptan concentration-effect curve was shifted by methiothepin (0.01 μM) to the right (pKB = 9.19) but not by ketanserin (1 μM). Concentration-effect curves to 5-HT and sumatriptan were not affected by the 5-HT3 receptor antagonist tropisetron (1 μM). These results suggest that 5-HT1-like type receptors are responsible for the first phase of 5-HT-induced contraction and 5-HT2A receptor for the second phase, in rabbit mesenteric artery. Sumatriptan-induced contractions appear to be mediated by 5-HT1-like type receptors in this artery. These results also suggest that this kind of amplification may be a common feature of vascular 5-HT1-like type receptor as has been shown in other vascular segments such as rabbit femoral, iliac and renal arteries, and guinea-pig iliac artery. © 1995, Springer-Verlag. All rights reserved.