Development of a primary culture system for rainbow trout corpuscles of stannius and characterization of secreted teleocalcin.

A primary culture system has been established for rainbow trout corpuscles of Stannius (CS). A RIA has also been developed to monitor and characterize the teleocalcin secreted by these cultures. The primary cultured CS cells actively synthesized and secreted teleocalcin for up to 39 days when maintained in amphibian and mammalian culture media. Numerous teleocalcin cells were also evident after immunocytochemical staining of the CS cultures. When the cultures were labeled with L-[35S]methionine, de novo synthesized and secreted teleocalcin was judged to be a glycosylated protein on the basis of Concanavalin-A-Sepharose binding and was similar in size to the intracellular form of the hormone. This culture system may prove to be ideal for identifying those factors that regulate teleocalcin secretion.