Monopoli A, Conti A, Forlani A, Ongini E, Antona C, Biglioli P
Research Laboratories, Schering-Plough SpA, Milan, Italy.
Cardiovasc Drugs Ther. 1990 Jan;4 Suppl 1:59-61. doi: 10.1007/BF00053428.
5-hydroxytryptamine (5HT) treatment produced dose-related contractions in the human internal mammary artery with an EC50 value of 3.4 X 10(-7) M. The 5HT2 receptor antagonist ketanserin reversed the contractions evoked by 5HT in a competitive manner at a low concentration (10(-8) M), whereas a noncompetitive antagonism was apparent at higher concentrations (5 X 10(-8) M to 5 X 10(-7) M). The alpha 1-blocking component of ketanserin was evaluated by studying the effect of ketanserin upon the contractile response evoked by norepinephrine. Up to 10(-7) M, ketanserin did not influence norepinephrine-induced contractions. These findings indicate that the mammary artery is a vascular tissue sensitive to contractions induced by 5HT and that the drug ketanserin antagonizes this contractile response through the 5HT2 receptor subtype.
5-羟色胺（5HT）处理可使人乳内动脉产生剂量相关的收缩，其半数有效浓度（EC50）值为3.4×10⁻⁷M。5HT₂受体拮抗剂酮色林在低浓度（10⁻⁸M）时以竞争性方式逆转5HT引起的收缩，而在较高浓度（5×10⁻⁸M至5×10⁻⁷M）时则表现出非竞争性拮抗作用。通过研究酮色林对去甲肾上腺素引起的收缩反应的影响来评估酮色林的α₁阻断成分。高达10⁻⁷M时，酮色林不影响去甲肾上腺素诱导的收缩。这些发现表明乳内动脉是对5HT诱导的收缩敏感的血管组织，且酮色林通过5HT₂受体亚型拮抗这种收缩反应。
