Cocaine- and amphetamine-regulated transcript peptide in the rat epididymis: An immunohistochemical and electrophysiological study
Cocaine- and amphetamine-regulated transcript peptide in the rat epididymis: An immunohistochemical and electrophysiological study
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DOI：
10.1095/biolreprod63.5.1518
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发表时间：
2000-11-01
影响因子：
3.6
通讯作者：
Chang, JK
中科院分区：
文献类型：
--
作者：
Dun, NJ;Dun, SL;Chang, JK
可卡因和安非他明调节的转录物（CART）是一个新的多肽家族，其中CART肽片段55-102和62-102被报道为内源性生理活性肽。用抗CART肽片段55-102的抗血清进行的免疫组织化学研究揭示了大鼠附睾中的CART样免疫反应性（CART-LI）神经纤维。附睾尾的CART-LI纤维数量最多，向附睾头逐渐减少;输精管显示出丰富的CART-LI纤维。注射逆行示踪剂荧光金（Fluorochrome，Inc.，Englewood，CO）到输精管和附睾尾之间的连接处标记了盆大神经节中的大量神经元，其中一些是CART阳性的。用酪氨酸羟化酶（TH）和CART抗血清双标记的神经节部分显示，CART-LI和TH-LI在两个不同的神经节细胞群体中表达。但在神经节内的TH阳性细胞中，有网状CART阳性终末覆盖。在培养的上皮细胞中评估CART肽55-102（本文称为CART）对短路电流（Isc）形式的阴离子分泌的影响。CART（1至5 μ M）应用于培养的上皮细胞的基底侧或顶侧引起的Isc没有显着的反应，而赖氨酸-缓激肽（1 μ M）在相同的制剂中产生了大的Isc反应。我们的研究结果表明，CART-LI是存在于人口的大鼠盆腔神经节细胞，这可能会引起CART-LI神经纤维中观察到的输精管和附睾。CART在大鼠附睾中的生物学功能尚不清楚，但它显然不参与跨上皮的离子分泌。
Cocaine- and amphetamine-regulated transcript (CART) is a novel family of peptides, of which CART peptide fragments 55-102 and 62-102 are reported to be the endogenous, physiologically active peptides. Immunohistochemical studies with an antiserum directed against the CART peptide fragment 55-102 revealed CART-like immunoreactive (CART-LI) nerve fibers in the rat epididymis. The number was highest in the cauda epididymis and became progressively fewer toward the caput epididymis; the vas deferens exhibited an abundance of CART-LI fibers. Injection of the retrograde tracer Fluorogold (Fluorochrome, Inc., Englewood, CO) to the junction between the vas deferens and cauda epididymis labeled a large number of neurons in the major pelvic ganglion, some of which were CART-positive. Double-labeling the ganglion sections with tyrosine hydroxylase (TH) and CART antisera revealed that CART-LI and TH-LI were expressed in two distinct populations of ganglion cells. Some of the TH-LI cells in the ganglia, however, were covered with weblike CART-LI endings. The effects of CART peptide 55-102, referred to herein as CART, on anion secretion in the form of short circuit currents (Isc) were assessed in cultured epithelia. The CART (1 to 5 muM) applied to the basolateral or apical side of the cultured epithelia caused no significant responses on Isc, whereas lys-bradykinin (1 muM) produced a large Isc response in the same preparations. Our results show that CART-LI is present in a population of rat pelvic ganglion cells, which may give rise to CART-LI nerve fibers as observed in the vas deferens and the epididymis. The biological function of CART in the rat epididymis is not known, but it apparently is not involved in ion secretion across the epithelium.