Effects of metopirone on the pars distalis, the interrenal gland and the testis of the frog, Rana cyanophlyctis (Schn.).

Administration (i.m.) of metopirone (2.5 mg/frog/day for 10 days) to adult male frog, R. cyanophlyctis, resulted in marked degranulation and hypertrophy of B3 cells and a moderate degranulation of B2 cells of the pars distalis. Concomitantly, there was hypertrophy of the interrenal cells and regression of the Leydig cells, however spermatogenesis was not affected. The results suggest a functional correlation between pituitary B cells and the interrenals in R. cyanophlyctis.