Steenstrup B R, Jørgensen J C, Alm P, Hannibal J, Junge J, Fahrenkrug J, Ottesen B
Department of Gynaecology and Obstetrics, Huidoure Hospital, University of Copenhagen, Denmark.
Regul Pept. 1996 Mar 22;61(3):197-204. doi: 10.1016/0167-0115(95)00156-5.
Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide which was originally isolated from ovine hypothalamus. PACAP exists in at least two biologically active forms, PACAP-38 and PACAP-27. The aim of this study was to establish the distribution, localization and smooth muscle effects of PACAP-38 and PACAP-27 in the human uteroplacental unit. For this purpose we used radioimmunoassay, immunocytochemistry and in vitro studies of the effect of the peptides on smooth muscle activity.
By radioimmunoassay both peptides were detected throughout the uteroplacental unit. The concentrations of PACAP-27 were in general low, ranging from 1/6-1/25 of the corresponding PACAP-38 concentrations. PACAP-immunoreactivity was localized in nerve fibres of the lower segment of the pregnant uterus, but the number of PACAP-immunoreactive nerves was very clearly reduced compared to the corresponding isthmic region of non-pregnant myometrial tissue. PACAP-immunoreactive fibres were not observed in placenta or in the umbilical cord. Both PACAP-38 and PACAP-27 caused a concentration-dependent relaxation on stem villous arteries and on the intramyometrial arteries. Neither of the peptides displayed any effect on non-vascular smooth muscle specimens from the term pregnant myometrium. In conclusion the findings suggest a vasoregulator role of PACAP in the human uteroplacental unit.
垂体腺苷酸环化酶激活多肽（PACAP）是一种最初从绵羊下丘脑分离出的神经肽。PACAP至少以两种生物活性形式存在，即PACAP - 38和PACAP - 27。本研究的目的是确定PACAP - 38和PACAP - 27在人子宫胎盘单位中的分布、定位及对平滑肌的作用。为此，我们采用放射免疫分析法、免疫细胞化学方法以及对肽对平滑肌活性影响的体外研究。
通过放射免疫分析法在整个子宫胎盘单位均检测到这两种肽。PACAP - 27的浓度总体较低，范围为相应PACAP - 38浓度的1/6至1/25。PACAP免疫反应性定位于妊娠子宫下段的神经纤维，但与非妊娠子宫肌层组织相应的峡部区域相比，PACAP免疫反应性神经的数量明显减少。在胎盘或脐带中未观察到PACAP免疫反应性纤维。PACAP - 38和PACAP - 27均引起绒毛干动脉和子宫肌层内动脉的浓度依赖性舒张。这两种肽对足月妊娠子宫肌层的非血管平滑肌标本均无任何作用。总之，这些发现提示PACAP在人子宫胎盘单位中具有血管调节作用。
