Rm. Uribe et al., PHORBOL ESTER OR CAMP ENHANCE THYROTROPIN-RELEASING-HORMONE MESSENGER-RNA IN PRIMARY CULTURES OF HYPOTHALAMIC CELLS, Neuroscience letters, 201(1), 1995, pp. 41-44
Thyrotropin releasing hormone (TRH) biosynthesis is subject to a multi
factorial control. TRH mRNA levels are negatively regulated by thyroid
hormones in the paraventricular hypothalamic nucleus, and positively
in cold exposure or suckling. Effect of second messenger pathways stim
ulation, a known response of membrane receptors, was studied in vitro;
cultures of rat embryonic hypothalami (is day gestation) were treated
with 12-O-tetradecanoylphorbol-13-acetate (TPA, 100 nM) or dibutiryl
cAMP (dBcAMP, 1 mM) for various times. Levels of TRH mRNA were raised
after the first hour of dBcAMP or 2 h of TPA treatment and were still
increased at 24 h. These results suggest a neural regulation of TRH bi
osynthesis.