Glucagon does not affect catecholamine release in primary cultures of bovine adrenal chromaffin cells.
Glucagon does not affect catecholamine release in primary cultures of bovine adrenal chromaffin cells.
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胰高血糖素不影响牛肾上腺嗜铬细胞原代培养物中儿茶酚胺的释放。
DOI：
10.1055/s-2005-861415
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Goldstein,DS
中科院分区：
文献类型：
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作者：
Sharabi,Y;Zimlichman,R;Alesci,S;Huynh,T;Mansouri,R;Chun,J;Perera,S;Pacak,K;Goldstein,DS
目的人嗜铬细胞瘤肿瘤细胞表达胰高血糖素受体，静脉推注胰高血糖素可迅速升高血浆肾上腺素水平，提示胰高血糖素可直接刺激肾上腺髓质分泌。在本研究中，我们测试了儿茶酚胺对胰高血糖素的分泌反应是否存在于牛嗜铬细胞中或仅存在于肿瘤细胞中。设计和方法将肾上腺髓质细胞培养在24孔板中（每孔10 6 个细胞）。 48-72小时后，将孔与(1)孵育培养基(对照)、(2)儿茶酚胺促分泌剂(尼古丁或钾离子)或(3)胰高血糖素(10-8至10-5M)一起孵育1-20分钟。孵育后，通过高压液相色谱和电化学检测来测定培养基和细胞中的儿茶酚胺含量。计算肾上腺素、去甲肾上腺素和多巴胺的部分释放率并与对照进行比较。采用逆转录酶PCR比较嗜铬细胞和嗜铬细胞瘤细胞中胰高血糖素受体mRNA的表达。结果尼古丁和钾引起肾上腺素、去甲肾上腺素和多巴胺的时间依赖性释放。任何浓度的胰高血糖素都不影响儿茶酚胺的分泌。逆转录酶PCR未能在牛肾上腺髓质细胞中检测到胰高血糖素受体的mRNA，但在人嗜铬细胞瘤细胞中检测到它。 结论与嗜铬细胞瘤细胞相反，牛肾上腺髓质嗜铬细胞不表达胰高血糖素受体，因此不会响应胰高血糖素分泌儿茶酚胺。
ObjectiveHuman pheochromocytoma tumor cells express glucagon receptors, and bolus iv glucagon injection rapidly increases plasma epinephrine levels, suggesting that glucagon can directly stimulate adrenomedullary secretion. In this study, we tested whether the catecholamine secretory response to glucagon was present in bovine chromaffin cells or exclusive to the tumor cells.Design and MethodsAdrenomedullary cells were cultured in 24-well plates (10 6 cells per well). After 48-72 hours, wells were incubated for 1-20 minutes with (1) incubation medium (control),(2) catecholamine secretagogues (nicotine or potassium ion), or (3) glucagon (10-8 to 10-5 M). After incubation, catecholamine contents in medium and cells were assayed by high-pressure liquid chromatography with electrochemical detection. Fractional release rates of epinephrine, norepinephrine, and dopamine were calculated and compared to controls. Reverse-transcriptase PCR was performed to compare expression of mRNA of the glucagon receptor in chromaffin cells and pheochromocytoma cells.ResultsNicotine and potassium evoked time-dependent release of epinephrine, norepinephrine, and dopamine. Glucagon did not affect catecholamine secretion at any concentration. Reverse-transcriptase PCR failed to detect mRNA for glucagon receptor in bovine adrenomedullary cells, but did detect it in human pheochromocytoma cells.ConclusionsIn contrast to pheochromocytoma tumor cells, bovine adrenomedullary chromaffin cells do not express the glucagon receptor, and therefore do not secrete catecholamines in response to glucagon.