Organ culture of normal and carcinogen-treated rat bladder.

A system for organ culture of rat bladder in defined medium, without serum, is described. Transitional epithelial morphology of normal bladder was well maintained in Waymouth's Medium MB 752/1, while Ham's Medium F12 caused marked epithelial hyperplasia. Hyperplastic epithelial states induced by in vivo administration of the carcinogen, N-methyl-N-nitrosourea, were well maintained in vitro during organ culture in Medium MB 752/1. The combination of hydrocortisone and insulin markedly inhibited the proliferative response of normal bladder epithelium grown in Medium F12.