Expression of Nuclear Hormone Receptors in the Rat Supraoptic Nucleus

To investigate the role of nuclear hormone receptors on neuropep-tide gene expression in the hypothalamo-neurohypophyseal system (HNS) of the rat, a survey was made of members of the nuclear hormone receptor superfamily that are expressed in the supraoptic nucleus (SON). A polymerase chain reaction cloning strategy based on homologies in the DNA-binding domain of AGGTCA-binding factors was devised for the identification of receptors in microdissected SON tissue. Cloning of the amplified products led to the identification of five true receptors, thyroid hormone receptor-a (THRo), retinoic acid receptor-o, retinoic acid receptor-y, retinoidxreceptor-cu, and retinoid X receptor-y, as well as four orphan receptors, apolipoprotein AI regulatory protein (ARP-11, chicken ovalbumin upstream promoter transcription factor I (COUP-TF I), estrogen-related receptor 2, and testis receptor 4 (TR4). Dot-blot screening of amplified gene fragmen