Luteotrphic capacity of TRH in the baboon.

An attempt was made to determine the synergistic effect of TRH stimulated prolactin with LH on the luteinization of corpus luteum in baboons. Four normally cycling female baboons were used in this study. Synthetic LHRH (100 micrograms) was given during the early luteal phase and blood samples were collected sequentially for assay of progestin. In additional experiments, 40 micrograms of synthetic TRH was given at 30 and 60 minutes after LHRH injection and blood samples were assayed for progestin. Injection of LHRH elevated the plasma level of progestin. Subsequent treatment with TRH in LHRH treated baboons enhanced the elevation of plasma progestin in three of four baboons. The evidence illustrates the nature of synergistic effect of prolactin with LH on the luteinization of corpus luteum in baboons.