Changes in germ cell adenylate cyclase and protein carboxyl methylase activities in rat testicular tissue during bilateral cryptorchidism and after orchidopexy.

Soluble Mn2+-dependent adenylate cyclase and protein carboxyl methylase are two enzymes that are primarily localized in haploid germ cels of rat testicular tissue, and both enzymes exhibit an increase in activity in association with sexual maturation. Experimental cryptorchidism (surgery at 17 days of age) in immature rats prevented the age-dependent increase in the activity of these two testicular enzymes. After orchidopexy at 34 days of age the activities of these two enzymes increased to normal control values in association with testicular growth. These observations show that biochemical markers such as soluble Mn2+-dependent adenylate cyclase and protein carboxyl methylase can be used to follow germ cell differentiation.