Comparison of corticotropin-releasing factor and acetylcholine on catecholamine secretion in dogs.
Comparison of corticotropin-releasing factor and acetylcholine on catecholamine secretion in dogs.
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DOI：
10.1152/ajpregu.1987.253.2.r209
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发表时间：
1987-08
期刊：
影响因子：
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通讯作者：
W. Engeland;M. Lilly;T. Bruhn;D. Gann
中科院分区：
文献类型：
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作者：
W. Engeland;M. Lilly;T. Bruhn;D. Gann
为了测试促肾上腺皮质激素释放因子（CRF）是否是肾上腺分泌儿茶酚胺的促分泌素，开发了一种制剂，其允许测量响应于体内动脉注射到狗肾上腺中的肾上腺静脉输出。在犬的腰肾上腺静脉中准备导管，用于监测肾上腺血流量和肾上腺素和去甲肾上腺素的分泌速率，并在腰肾上腺和膈下动脉中准备导管，用于肾上腺注射。在手术后48小时戊巴比妥麻醉下，犬接受一系列肾上腺内注射，包括乙酰胆碱（0.2-200 nmol）、CRF（2.0-20.0 nmol）和稀释剂。在肾上腺素分泌和去甲肾上腺素分泌对乙酰胆碱之前存在对数剂量反应关系。肾上腺注射CRF刺激肾上腺素和去甲肾上腺素分泌的最高剂量测试（20 nmol）。观察到的反应相当于对0.2 nmol乙酰胆碱的反应。全身给予相似剂量的CRF可产生低血压，而不刺激儿茶酚胺反应。肾上腺儿茶酚胺对乙酰胆碱的反应并不因CRF的加入而增强。这些结果表明，动脉注射CRF到完整的狗肾上腺刺激肾上腺素和去甲肾上腺素的分泌。然而，CRF相对于乙酰胆碱的效力较低，CRF对乙酰胆碱的儿茶酚胺反应缺乏协同作用，以及达到反应所需的高剂量CRF表明CRF在肾上腺髓质中不起生理学上重要的儿茶酚胺促分泌素的作用。
To test whether corticotropin-releasing factor (CRF) is a secretagogue for adrenal secretion of catecholamines, a preparation was developed that permits measurement of adrenal venous output in response to in vivo arterial injection into the dog adrenal gland. Dogs were prepared with catheters in the lumboadrenal vein for monitoring adrenal blood flow and secretion rate of epinephrine and norepinephrine and in the lumboadrenal and inferior phrenic arteries for adrenal injection. Under pentobarbital anesthesia 48 h after surgery, dogs received a series of intra-adrenal injections that included acetylcholine (0.2-200 nmol), CRF (2.0-20.0 nmol), and diluent. There was a log dose-response relationship before epinephrine secretion and norepinephrine secretion to acetylcholine. Adrenal injection of CRF stimulated epinephrine and norepinephrine secretion at the highest dose tested (20 nmol). The response observed was equivalent to the response to 0.2 nmol acetylcholine. A similar dose of CRF given systemically produced hypotension without stimulating catecholamine responses. Adrenal catecholamine responses to acetylcholine were not augmented by addition of CRF. These findings show that arterial injection of CRF into the intact dog adrenal stimulates secretion of epinephrine and norepinephrine. However, the low potency of CRF relative to that of acetylcholine, the lack of a synergistic effect of CRF on catecholamine responses to acetylcholine, and the high dose of CRF required to achieve a response suggest that CRF does not function in the adrenal medulla as a physiologically important secretagogue for catecholamines.