The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
Am J Physiol Regul Integr Comp Physiol. 2013 Jun 1;304(11):R940-50. doi: 10.1152/ajpregu.00257.2012. Epub 2013 Apr 3.
Barrington's nucleus, in the pons, regulates micturition through spinal projections to preganglionic parasympathetic neurons. The stress neuropeptide CRF is prominent in these projections and has an inhibitory influence. Social stress in rats causes urinary retention and abnormal urodynamics resembling those produced by partial bladder outlet obstruction (pBOO), and this is associated with CRF upregulation in Barrington's nucleus. Here, we examined the role of CRF in social stress- and pBOO-induced urodynamic dysfunction by assessing the ability of a CRF₁ receptor antagonist to alter these effects. Male rats exposed to repeated resident-intruder stress were administered vehicle or a CRF₁ antagonist (NBI-30775) daily prior to the stress. Urodynamic function was recorded in the unanesthetized state 72 h after the final stress. NBI-30775 prevented the increased intermicturition interval, micturition volume, and bladder capacity produced by social stress, but not the increase in CRF expression in Barrington's nucleus neurons. The urinary dysfunction was also partly prevented by shRNA targeting of CRF in Barrington's nucleus, suggesting that stress-induced urinary dysfunction results, in part, from CRF upregulation in Barrington's nucleus and enhanced postsynaptic effects in the spinal cord. Finally, NBI-30775 improved urodynamic function of rats that had pBOO of 2-wk duration when administered daily during the second week but did not block the increase in CRF expression in Barrington's nucleus neurons. These findings implicate a role for Barrington's nucleus CRF in stress- and pBOO-induced urodynamic changes and suggest that CRF₁ antagonists may be useful therapeutic agents for the treatment of urinary dysfunction.
脑桥臂旁核通过向节前副交感神经元的脊髓投射来调节排尿。应激神经肽 CRF 在这些投射中很突出,并具有抑制作用。大鼠的社会应激导致尿潴留和异常的尿动力学,类似于部分膀胱出口梗阻(pBOO)产生的尿动力学,这与脑桥臂旁核中的 CRF 上调有关。在这里,我们通过评估 CRF₁ 受体拮抗剂改变这些效应的能力,研究了 CRF 在社会应激和 pBOO 诱导的尿动力学功能障碍中的作用。雄性大鼠在暴露于反复的居民入侵者应激之前,每天接受载体或 CRF₁ 拮抗剂(NBI-30775)的治疗。在最后一次应激后 72 小时,在未麻醉状态下记录尿动力学功能。NBI-30775 可防止社交应激引起的排尿间隔、排尿量和膀胱容量增加,但不能防止脑桥臂旁核神经元中 CRF 表达增加。CRF 在脑桥臂旁核中的 shRNA 靶向也部分预防了尿功能障碍,这表明应激引起的尿功能障碍部分是由于脑桥臂旁核中的 CRF 上调和脊髓中的突触后效应增强所致。最后,当在第二周每天给予时,NBI-30775 可改善持续 2 周的 pBOO 大鼠的尿动力学功能,但不能阻止脑桥臂旁核神经元中 CRF 表达的增加。这些发现表明,脑桥臂旁核 CRF 在应激和 pBOO 诱导的尿动力学变化中起作用,并表明 CRF₁ 拮抗剂可能是治疗尿功能障碍的有用治疗剂。