Kachadorian W A, Ellis S J, Muller J
Am J Physiol. 1979 Jan;236(1):F14-20. doi: 10.1152/ajprenal.1979.236.1.F14.
Intramembranous particle aggregates in the luminal membrane of toad bladder granular cells after vasopressin stimulation have been found to correlate closely and specifically with induced alterations of water permeability. Roles for microtubules and microfilaments in mediating the latter response have been proposed on the basis of studies involving colchicine and cytochalasin B, respectively. In the present investigation the effects of these agents on both initiating and sustaining vasopressin-induced osmotic water flow and the particle aggregation phenomenon were studied. The results indicate that during initiation the aggregation and water flow responses to vasopressin are each colchicine- and cytochalasin B-sensitive and that these sensitivities can be wholly additive. However, after full vasopressin stimulation is established, the same responses demonstrate sensitivity only to cytochalasin B, not to colchicine. The findings, therefore, suggest that microtubules and microfilaments may be independently necessary for the initiation of the aggregation and water flow responses to vasopressin, and that microfilaments, but not microtubules, are required for their maintenance.
已发现，血管加压素刺激后蟾蜍膀胱颗粒细胞管腔膜中的膜内颗粒聚集体与诱导的水通透性改变密切且特异性相关。分别基于涉及秋水仙碱和细胞松弛素B的研究，有人提出微管和微丝在介导后一种反应中起作用。在本研究中，研究了这些药物对启动和维持血管加压素诱导的渗透水流动以及颗粒聚集现象的影响。结果表明，在启动过程中，对血管加压素的聚集和水流动反应对秋水仙碱和细胞松弛素B均敏感，且这些敏感性可完全叠加。然而，在建立完全的血管加压素刺激后，相同的反应仅对细胞松弛素B敏感，对秋水仙碱不敏感。因此，这些发现表明，微管和微丝对于启动对血管加压素的聚集和水流动反应可能是独立必需的，并且维持这些反应需要微丝而非微管。
