Effects of the antidiuretic hormone, arginine vasotocin, theophylline, filipin and A23187 on cyclic AMP in isolated frog skin epithelium (Rana temporaria).
Effects of the antidiuretic hormone, arginine vasotocin, theophylline, filipin and A23187 on cyclic AMP in isolated frog skin epithelium (Rana temporaria).
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抗利尿激素、精氨酸催产素、茶碱、菲律宾素和 A23187 对离体青蛙皮肤上皮 (Rana temporaria) 环磷酸腺苷的影响。
DOI：
10.1111/j.1748-1716.1978.tb06075.x
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发表时间：
1978
期刊：
影响因子：
--
通讯作者：
R. Nielsen
中科院分区：
文献类型：
--
作者：
A. Johnsen;R. Nielsen
建立了蛙皮肤上皮细胞cAMP含量的测定方法。胶原酶处理后分离上皮细胞。通过沸水提取cAMP，并将提取物在干燥的Al 2 O3上纯化。本文观察了精氨酸缩血管素（AVT）作用后cAMP水平随时间的变化。激素引起cAMP水平迅速升高，3-5分钟后达到最大值，随后cAMP水平下降。用AVT孵育使上皮对第二剂量的AVT不敏感，这表明cAMP水平的下降是由反馈机制引起的，而不是由激素的失活引起的。cAMP在AVT刺激前后均均匀分布于上皮细胞各层。茶碱引起的cAMP水平，保持升高至少45分钟的快速增加。另外的离子载体A23187或菲律宾没有影响的cAMP水平。然而，在茶碱的存在下，A23187增强cAMP水平，而菲律宾没有效果。因此，必须考虑cAMP参与A23187的作用。
A method for measuring cAMP in frog skin epithelium was developed. The epithelia were isolated after collagenase-treatment. cAMP was extracted by boiling water and the extract was purified on dry Al2O3. The change with time of the cAMP level after addition of arginine vasotocin (AVT) was studied. The hormone caused a rapid increase in cAMP level with a maximum after 3-5 min, whereafter the cAMP level declined. Incubation with AVT made the epithelia refractory to a second dose of AVT, which indicates that the decline in cAMP level was caused by a feedback mechanism and not by inactivation of the hormone. cAMP appeared evenly distributed in all cell-layers of the epithelia both before and after stimulation with AVT. Theophylline caused a rapid increase in the cAMP level, which remained elevated for at least 45 min. Addition of the ionophore A23187 or of filipin had no effect on the cAMP level. However, in the presence of theophylline, A23187 enhanced the cAMP level, whereas filipin had no effect. Therefore the involvement of cAMP in the action of A23187 has to be considered.