Hiroyuki Nogi, Hitoshi Hashimoto, Takashi Fujita, Nami Hagihara, Toshio
Matsuda and Akemichi Baba (*)
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565, Japan
(*) To whom correspondence should be addressed.
Abstract: The distribution of mRNA for pituitary adenylate cyclase-activating polypeptide receptor (PACAP-R) was examined by in situ hybridization in rat adrenal gland. In the adrenal medulla, PACAP-R mRNA was expressed in almost all chromaffin cells without any significant expression in the cortical region. Using the reverse transcription-polymerase chain reaction, we analyzed the mRNA expression of PACAP-R splice variant forms in the adrenal gland. The predominant forms observed were the variant having a 28-amino acid insert in the third intracellular loop (termed PACAP-R-hop1). As PACAP is localized in the noradrenaline secreting cells of the adrenal chromaffin cells, and stimulates catecholamine release, the present results suggest that PACAP may serve as a paracrine or autocrine regulatory factor for the chromaffin cells through PACAP-R.
Keywords: PACAP (pituitary adenylate cyclase-activating polypeptide)/VIP (vasoactive intestinal polypeptide) receptor mRNA expression, In situ hybridization, Adrenal gland