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