Schicho R, Kanai Y, Ishikawa T, Skofitsch G, Donnerer J
Department of Experimental and Clinical Pharmacology, University of Graz, Austria.
J Auton Nerv Syst. 1998 Aug 27;73(1):46-53. doi: 10.1016/s0165-1838(98)00125-8.
Neonatal denervation of primary afferents with capsaicin leads to increased sympathetic innervation of the rat ureter. In the present study the development and the immunohistochemical characterization of this sympathetic hyperinnervation as well as the specific involvement of nerve growth factor (NGF) was investigated. Noradrenaline levels were found elevated in neonatally capsaicin-treated rats by 2 weeks of age and remained at that high level into adulthood. Injections of an anti-NGF antiserum during postnatal days (PN) PN 8-14, PN 13-19 or during PN 17-23 counteracted the capsaicin effect and reduced noradrenaline towards control levels. Immunohistochemical localization of tyrosine hydroxylase (TH), a marker for sympathetic nerve fibres, revealed that the capsaicin-induced hyperinnervation was mainly represented by fibres in deeper muscle layers and to a smaller extent by fibres in the submucosa. In control animals and in rats treated with capsaicin and anti-NGF antiserum fibres were mainly distributed in the adventitia and in the outer part of the smooth muscle layer. These results show that NGF is responsible for the development of an increased noradrenergic innervation in the rat ureter after neonatal capsaicin treatment.
用辣椒素对初级传入神经进行新生期去神经支配会导致大鼠输尿管的交感神经支配增加。在本研究中，对这种交感神经超支配的发育和免疫组织化学特征以及神经生长因子（NGF）的具体作用进行了研究。发现新生期用辣椒素处理的大鼠在2周龄时去甲肾上腺素水平升高，并在成年期一直保持在高水平。在出生后第（PN）8 - 14天、PN 13 - 19天或PN 17 - 23天注射抗NGF抗血清可抵消辣椒素的作用，并使去甲肾上腺素水平降至对照水平。酪氨酸羟化酶（TH）是交感神经纤维的标志物，其免疫组织化学定位显示，辣椒素诱导的超支配主要由深层肌肉层中的纤维代表，黏膜下层中的纤维占比小。在对照动物以及用辣椒素和抗NGF抗血清处理的大鼠中，纤维主要分布在外膜和平滑肌层的外部。这些结果表明，NGF是新生期辣椒素处理后大鼠输尿管中去甲肾上腺素能神经支配增加的发育原因。
