Pituitary adenylate cyclase activating polypeptide: occurrence and relaxant effect in the human female reproductive tract. Steenstrupa, Birgit Ravn, Per Almd, Jens Hannibal, Jorgen Christen Jorgensen, Connie Palle, Jette Junge, Hanne Borch Christensen, Bent Ottesen, and Jan Fahrenkrug. Departments of Gynaecology and Obstetrics, Hvidovre, Herlev and Glostrup Hospitals, University of Copenhagen, Denmark, Department of Pathology and Cytology, University of Lund, Sweden, Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen and Department of Pathology and Cytology, Hvidovre Hospital, University of Copenhagen, Denmark
APStracts 2:0039E, 1995.
The distribution, localization and smooth muscle effects of pituitary adenylate cyclase activating polypeptide (PACAP) were studied in the human female genital tract. The concentrations of PACAP-38 and PACAP -27 were measured by radioimmunoassays and both peptides were found throughout the genital tract. The highest concentrations of PACAP-38 were detected in the ovary, the upper part of vagina and in the perineum. The concentrations of PACAP-27 were generally low, in some regions below the detection limit and in other regions 1/20 to 1/100 of the PACAP-38 concentrations. Immunocytochemistry revealed that PACAP was located in delicate varicose nerve fibres which were most abundant in the internal cervical os where they mainly seemed to innervate blood vessels and smooth muscle cells. PACAP-38 and PACAP -27 (10-10 - 10-6 M) caused a concentration dependent relaxation of the spontaneous activity of the non-vascular smooth muscle strips from Fallopian tube and myometrium in vitro. Likewise, both peptides (10-10 - 10-6 M) caused relaxation of norepinephrine (NE) (10-6 M) precontracted intramyometrial arteries. No effect of the PACAP -sequences, PACAP 6-27, PACAP 16-38 and PACAP 18-27 on Fallopian tube was observed. The findings suggest a smooth muscle regulatory role of PACAP in the human female reproductive tract.

Received 5 December 1994; accepted in final form 17 February
1995.
APS Manuscript Number E507-4.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  1 March 1995.