Gonadal hormones affect diameter of male rat cerebral arteries through endothelium-dependent mechanisms
Gonadal hormones affect diameter of male rat cerebral arteries through endothelium-dependent mechanisms
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DOI：
10.1152/ajpheart.2000.279.2.h610
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发表时间：
2000-08-01
影响因子：
4.8
通讯作者：
Duckles, SP
中科院分区：
文献类型：
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作者：
Geary, GG;Krause, DN;Duckles, SP
众所周知，性别会影响脑血管疾病的发病率和严重程度。在本研究中，体外测量了未治疗、睾丸切除 (ORX)、ORX 睾酮治疗 (ORX+TEST) 或 ORX 雌激素治疗 (ORX+EST) 雄性大鼠受压大脑中动脉段的管腔直径。所有四组的动脉最大被动直径 (0 Ca2+ + 3 mM EDTA) 相似。在内皮完整的动脉中，与来自 ORX 或 ORX+EST 的动脉相比，来自未治疗和 ORX+TEST 的动脉的肌源性张力显着更大。在暴露于 N-G-硝基-L-精氨酸甲酯 (L-NAME)（一种 NO 合酶 (NOS) 抑制剂）期间，所有组的肌原性张力均显着增加。与来自 ORX 和 ORX+TEST 大鼠的动脉相比，L-NAME 在未经治疗和 ORX+EST 大鼠的动脉中的作用显着更大。抑制 NOS 后，ORX 和 ORX+TEST 之间的肌源性张力差异仍然存在。去除内皮或抑制环氧合酶途径并结合 K+ 通道阻滞剂后，ORX 和 ORX+TEST 之间的肌源性张力差异被消除。 ORX 和 ORX+TEST 的动脉之间的壁厚度和强制扩张没有显着差异。我们的数据表明，性腺激素通过 NOS 和/或内皮依赖性机制影响雄性大鼠脑动脉的肌原性张力。
Gender is known to influence the incidence and severity of cerebrovascular disease. In the present study, luminal diameter was measured in vitro in pressurized middle cerebral artery segments from male rats that were either untreated, orchiectomized (ORX), ORX with testosterone treatment (ORX+TEST), or ORX with estrogen treatment (ORX+EST). The maximal passive diameters (0 Ca2+ + 3 mM EDTA) of arteries from all four groups were similar. In endothelium-intact arteries, myogenic tone was significantly greater in arteries from untreated and ORX+TEST compared with arteries from either ORX or ORX+EST. During exposure to N-G-nitro-L-arginine-methyl ester (L-NAME), an NO synthase (NOS) inhibitor, myogenic tone significantly increased in all groups. The effect of L-NAME was significantly greater in arteries from untreated and ORX+EST compared with arteries from ORX and ORX+TEST rats. Differences in myogenic tone between ORX and ORX+TEST persisted after inhibition of NOS. After endothelium removal or inhibition of the cyclooxygenase pathway combined with K+ channel blockers, myogenic tone differences between ORX and ORX+TEST were abolished. Wall thickness and forced dilation were not significantly different between arteries from ORX and ORX+TEST. Our data show that gonadal hormones affect myogenic tone in male rat cerebral arteries through NOS- and/or endothelium-dependent mechanisms.