离体猴肠系膜静脉与动脉对组胺和乙酰胆碱的反应。

Responses to histamine and acetylcholine in isolated monkey mesenteric veins versus arteries.

作者信息

Okamura T, Yamazaki M, Toda N

机构信息

Department of Pharmacology, Shiga University of Medical Science, Ohtsu, Japan.

出版信息

Cardiovasc Res. 1994 May;28(5):667-72. doi: 10.1093/cvr/28.5.667.

DOI:10.1093/cvr/28.5.667

PMID:8025911

Abstract

OBJECTIVE

The aim was to analyse and compare mechanisms of histamine or acetylcholine action in mesenteric venous and arterial strips obtained from Japanese monkeys.

METHODS

Monkey mesenteric arterial and venous strips were suspended for isometric tension recording in modified Ringer-Locke solutions, and responses of the strips precontracted with prostaglandin F2 alpha to histamine or acetylcholine were compared.

RESULTS

Histamine (2 x 10(-8) M-10(-5) M) produced a concentration related relaxation in the arteries and veins. The arterial relaxation was slightly but significantly attenuated by endothelial denudation [57.1(SEM 11.2)% inhibition at 10(-7) M, n = 14, p < 0.05] and treatment with 10(-6) M chlorpheniramine [26.7(6.7)% inhibition at 10(-7) M, n = 10, p < 0.05] or 10(-5) M methylene blue [31.5(11.2)% inhibition at 10(-7) M, n = 9, p < 0.05], and markedly suppressed by 10(-5) M cimetidine [96.8(1.2)% inhibition at 10(-7) M, n = 13, p < 0.001]. Indomethacin (10(-6) M) was without effect. On the other hand, relaxant responses to histamine of the venous strips were not influenced by endothelial denudation and treatment with chlorpheniramine or indomethacin but were abolished by treatment with cimetidine. Removal of the endothelium did not alter the venous relaxation caused by acetylcholine (10(-8) M-10(-4) M) but almost abolished the response to Ca2+ ionophore A23187 (10(-7) M) and substance P (10(-7) M). The acetylcholine induced relaxation was reversed to a contraction by indomethacin.

CONCLUSIONS

Histamine-induced relaxations of monkey mesenteric arteries seem to be associated mainly with activation of the H2 receptor subtype in smooth muscle and partially mediated by relaxing factor liberated by stimulation of the H1 subtype in the endothelium, whereas the mesenteric venous relaxation seems to be due exclusively to a mediation of H2 receptors. Acetylcholine-induced relaxations of venous strips appear to be caused by vasodilator prostanoids, possibly prostaglandin I2, liberated from subendocardial tissues.

摘要

目的

分析并比较组胺或乙酰胆碱对日本猕猴肠系膜静脉和动脉条带的作用机制。

方法

将猕猴肠系膜动脉和静脉条带悬挂于改良的林格 - 洛克溶液中进行等长张力记录，比较用前列腺素F2α预收缩后的条带对组胺或乙酰胆碱的反应。

结果

组胺（2×10⁻⁸M - 10⁻⁵M）使动脉和静脉产生浓度相关的舒张。内皮剥脱[在10⁻⁷M时抑制率为57.1（标准误11.2）%，n = 14，p < 0.05]、用10⁻⁶M氯苯那敏处理[在10⁻⁷M时抑制率为26.7（6.7）%，n = 10，p < 0.05]或10⁻⁵M亚甲蓝处理[在10⁻⁷M时抑制率为31.5（11.2）%，n = 9，p < 0.05]可使动脉舒张略有但显著减弱，而10⁻⁵M西咪替丁可显著抑制[在10⁻⁷M时抑制率为96.8（1.2）%，n = 13，p < 0.001]。吲哚美辛（10⁻⁶M）无作用。另一方面，静脉条带对组胺的舒张反应不受内皮剥脱及氯苯那敏或吲哚美辛处理的影响，但可被西咪替丁处理消除。去除内皮不改变乙酰胆碱（10⁻⁸M - 10⁻⁴M）引起的静脉舒张，但几乎完全消除对Ca²⁺离子载体A23187（10⁻⁷M）和P物质（10⁻⁷M）的反应。吲哚美辛可使乙酰胆碱诱导的舒张转变为收缩。