多塞平对离体兔基底动脉环和隐动脉环的作用

Effects of doxepin on isolated basilar and saphenous artery rings of rabbits

目的：观察多塞平（ｄｏｘｅｐｉｎ，Ｄｏｘ）对兔脑血管的作用．方法：采用离体兔基底动脉和隐动脉动脉环离体实验方法．结果：多塞平抑制ＫＣｌ４５．６ｍｍｏｌ·Ｌ－１和５羟色胺１０μｍｏｌ·Ｌ－１诱发的兔基底动脉环和隐动脉环收缩，其拮抗ＣａＣｌ２量效反应的ｐＤ２值分别为５．２８±０．４０和４．７６±０．１４（ｎ＝６，Ｐ＜００１）．多塞平５．８μｍｏｌ·Ｌ－１抑制在无Ｃａ２＋液中去甲肾上腺素引起的隐动脉环收缩，多塞平３０μｍｏｌ·Ｌ－１对无Ｃａ２＋液中去甲肾上腺素和恢复正常Ｃａ２＋液（１．２５ｍｍｏｌ·Ｌ－１）引起的隐动脉环收缩均有抑制作用．结论：与隐动脉环相比较。

AIM: To study the effects of doxepin (Dox) on cerebral artery. METHODS: The effects of Dox were observed using the isolated basilar and saphenous artery rings of rabbits. RESULTS: Dox inhibited the constriction of the basilar and saphenous artery rings evoked by KCl with IC50 5.75 mu mol . L-1 (95% confidence limits were 2.3 - 14 mu mol . L-1, n = 8) and 34.6 mu mol . L-1 (95% confidence limits were 3.8 - 316 mu mol L-1, n = 8), respectively. Dox also inhibited the constriction of the basilar and saphenous artery rings of the rabbits stimulated by 5-hydroxytryptamine (5-HT), IC50 were 6.3 mu mol . L-1 (95% confidence limits were 1.7 - 23.3 mu mol . L-1, n = 7) and 8.0 (mu mol . L-1(95% confidence limits were 6.3 - 10.3 mu mol . L-1, n = 6), respectively. In both samples (basilar and saphenous artery rings) CaCl2 evoked, the pD(2) of Dox was 5.28 +/- 0.40 and 4.76 +/- 0.14, respectively (n = 6, P < 0.01). Dox 5.8 mu mol L-1 inhibited the constriction of the saphenous artery evoked by norepinephrine (NE) in Ca2+-free medium. Dox 30 mu mol . L-1 inhibited the constriction of the saphenous artery evoked both by NE and by readmission of CaCl2 (1.25 mmol L-1). CONCLUSION: As compared with its effect on the saphenous artery, Dox selectively inhibited the basilar artery.