Gray J A, Kavlock R J, Seidler F J, Slotkin T A
Developmental Toxicology Division, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711.
J Dev Physiol. 1991 Jun;15(6):325-30.
Peripheral sympathetic neurons are thought to provide trophic regulatory signals for development of their target tissues. In the current study, we investigated the role of sympathetic tone in the functional development of the kidney in rats, using neonatal intracisternal administration of 6-hydroxydopamine (6-OHDA). This treatment destroys central catecholaminergic pathways and permanently reduces sympathetic activity without ablating peripheral nerve terminals. Renal function was evaluated over the first two postnatal weeks, when glomerular and tubular function undergo rapid development. Although basal renal clearance and the homeostatic response to fluid deprivation developed normally in the lesioned rats, the response to a maximally-effective dose of desmopressin acetate (DDAVP), a vasopressin analog, became deficient by the end of the second week. After weaning, the lesioned animals were unable to survive a chronic salt load, which requires sustained water reabsorption but high output of sodium. These data indicate that normal sympathetic tone is required for appropriate development of the responsiveness of the renal tubule to vasopressin.
外周交感神经元被认为为其靶组织的发育提供营养调节信号。在本研究中,我们使用新生大鼠脑池内注射6-羟基多巴胺(6-OHDA)来研究交感神经张力在大鼠肾脏功能发育中的作用。这种处理破坏中枢儿茶酚胺能通路并永久性降低交感神经活性,而不破坏外周神经末梢。在出生后的前两周对肾功能进行评估,此时肾小球和肾小管功能正在快速发育。尽管损伤大鼠的基础肾清除率和对禁水的稳态反应正常发育,但到第二周结束时,对最大有效剂量的醋酸去氨加压素(DDAVP,一种血管加压素类似物)的反应变得不足。断奶后,损伤动物无法承受慢性盐负荷,这需要持续的水重吸收但高钠排泄。这些数据表明,正常的交感神经张力是肾小管对血管加压素反应性正常发育所必需的。