Liu Qiuli, Wong-Riley Margaret T T
Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
Respir Physiol Neurobiol. 2019 Jan;259:149-155. doi: 10.1016/j.resp.2018.10.005. Epub 2018 Oct 22.
The pituitary adenylate cyclase-activating polypeptide (PACAP) plays an important role in anterior pituitary hormone secretion, neurotransmission, and the control of breathing. Mice lacking PACAP die suddenly mainly in the 2 postnatal week, coinciding temporally with a critical period of respiratory development uncovered by our laboratory in the rat. The goal of the current study was to test our hypothesis that PACAP expression is reduced during the critical period in normal rats. We undertook immunohistochemistry and optical densitometry of PACAP (specifically PACAP38) in several brain stem respiratory-related nuclei of postnatal days P2-21 rats, and found that PACAP immunoreactivity was significantly reduced at P12 in the pre-Bötzinger complex, nucleus ambiguus, hypoglossal nucleus, and the ventrolateral subnucleus of the nucleus tractus solitarius. No changes were observed in the control, non-respiratory cuneate nucleus at P12. Results imply that the down-regulation of PACAP during normal postnatal development may contribute to the critical period of vulnerability, when the animals' response to hypoxia is at its weakest.
垂体腺苷酸环化酶激活多肽（PACAP）在前垂体激素分泌、神经传递及呼吸控制中发挥重要作用。缺乏PACAP的小鼠主要在出生后第2周突然死亡，这在时间上与我们实验室在大鼠中发现的呼吸发育关键期相吻合。本研究的目的是验证我们的假设，即正常大鼠在关键期PACAP表达会降低。我们对出生后第2 - 21天大鼠的几个脑干呼吸相关核团进行了PACAP（特别是PACAP38）的免疫组织化学和光密度测定，发现前包钦格复合体、疑核、舌下神经核和孤束核腹外侧亚核在出生后第12天PACAP免疫反应性显著降低。在出生后第12天的对照非呼吸楔束核中未观察到变化。结果表明，正常出生后发育过程中PACAP的下调可能导致动物对缺氧反应最弱的脆弱关键期。
