Handler J S, Preston A S
J Membr Biol. 1976 Feb 17;26(1):43-50. doi: 10.1007/BF01868865.
The epithelial cells of the toad urinary bladder are morphologically heterogenous. In order to relate the effect of vasopressin on cyclic AMP metabolism to cell type, the epithelial cells were separated by the density gradient technique of Scott, Sapirstein and Yoder (Science 184:797, 1974). The separation was verified by electron-microscopy and by observing that the band of cells enriched in mitochondria-rich cells was enriched in carbonic anhydrase activity compared to the band of granular cells. A large portion of cells collected from the gradient was considered to be nonviable, precluding further study of their function as intact cells. Vasopressin-stimulated adenylate cyclase activity in homogenates of granular cells was simular to that in homogenates of mitochondria-rich cells. Cyclic nucleotide phosphodiesterase activity was also similar in the two types of cell. Thus, the enzymes known to be involved in cyclic AMP metabolism in response to vasopressin appear to be located in both major cell types.
蟾蜍膀胱的上皮细胞在形态上是异质的。为了将抗利尿激素对环磷酸腺苷代谢的影响与细胞类型联系起来，采用了Scott、Sapirstein和Yoder（《科学》184:797，1974）的密度梯度技术分离上皮细胞。通过电子显微镜以及观察富含线粒体的细胞带与颗粒细胞带相比碳酸酐酶活性增强，证实了这种分离。从梯度中收集的大部分细胞被认为是无活力的，这排除了对其作为完整细胞功能的进一步研究。颗粒细胞匀浆中抗利尿激素刺激的腺苷酸环化酶活性与富含线粒体的细胞匀浆中的相似。两种类型细胞中的环核苷酸磷酸二酯酶活性也相似。因此，已知参与抗利尿激素诱导的环磷酸腺苷代谢的酶似乎存在于两种主要细胞类型中。
