Somatotropic actions of the homologous growth hormone and prolactins in the euryhaline teleost, the tilapia, Oreochromis mossambicus

摘要

It is increasingly clear that growth hormone (GH) has growth-promoting effects in fishes, which are me- diated in part by the insulin-like growth factor (IGF)-I. Growth-promoting actions of prolactin (PRL) have been reported in higher vertebrates, but are less well established in teleosts. We examined the effects of injecting homologous GH or the two homologous tilapia PRLs (tPRL_177 and tPRL_188) on the in vitro incorporation of [~35S]sulfate (extracellular matrix synthesis) and [~3H]thymidine (DNA synthesis) by cerato- branchial cartilage explants and on IGF-I mRNA levels in tilapia liver.