DISTRIBUTION OF THYROTROPIN-RELEASING-HORMONE RECEPTOR MESSENGER-RNA IN RAT PERIPHERAL-TISSUES

Since the thyrotropin-releasing hormone receptor (TRH-R) cDNA was isol ated, the distribution of TRH-R mRNA has been investigated in the cent ral nervous system (CNS) and the pituitary. However, there has been le ss genetical studies on the distribution of TRH-R mRNA in the peripher al tissues, although TRH exists not only in CNS but also in the periph eral tissues, In this study we investigated the distribution of TRH-R mRNA in rat peripheral tissues by reverse transcription-polymerase cha in reaction (RT-PCR) and Northern blot analysis. TRH-R mRNA was detect ed in almost all of the peripheral tissues tested, although the amount varied considerably depending on the tis sues. In the uterus, thymus, ovary, and testis, TRH-R mRNA levels appeared to be relatively high. These results suggest that TRH and its receptor have specific function s in the peripheral tissues as well as in CNS and in the pituitary.