Abstract
Proximal tuble cells which were isolated from the rat kidney and maintained in culture medium grew to conflence at day 4. Gap junctional intracellular communication (GJIC) also developed, which was indicated by the dye-coupling and electrical coupling between adjacent cells. Calmodulin-Ca2+ complex (CaM-Ca) blocked the GJIC. NOC 7(10μM), one of NO donors, also blocked GJIC. These results suggerst that intracellular Ca2+ and NO production regulates gap junction channels. It was known that cadmium (Cd) accumulates in the kidney and causes renal injury. Dye coupling between cells was significantly reduced 30 minutes after exposure to 100 μM Cd and disappeared completely after 60 minutes. Howecer, the Cd exposure did not bigin to affect the cell morphology until 60 minutes after exposure. The inhibiting effect of Cd on GJIC is avoidance from nephrotoxicity by Cd. [Jpn J Physiol 54 Suppl:S67 (2004)]
