Willoughby J O, Brogan M, Kapoor R
Centre for Neuroscience, Flinders Medical Centre, Bedford Park, Australia.
Neuroendocrinology. 1989 Nov;50(5):584-91. doi: 10.1159/000125285.
Combined immunohistochemical labelling for neurons containing growth hormone (GH) releasing factor (GRF) or somatostatin and single labelling immunohistochemistry combined with Fluorogold retrograde transport labelling were used to examine whether somatostatin or GRF neurons might be reciprocally innervated. Occasional somatostatin-immunoreactive neurons in the periventricular preoptic area were found to be closely approached by GRF-immunoreactive fibres, providing possible evidence of scant innervation of somatostatin neurons by GRF cells. In contrast, many GRF-immunoreactive neurons in the arcuate nucleus appeared to have somatostatin-immunoreactive fibres closely applied to their perikarya suggesting that GRF neurons might be innervated by somatostatin cells. Combined retrograde tracing and fluorescence immunohistochemistry revealed few somatostatin-immunoreactive neurons doubly labelled following injections of Fluorogold in the basal hypothalamus. Occasional GRF-immunoreactive neurons in the basal hypothalamus were doubly labelled following PO/AHA injections of Fluorogold. Numerous somatostatin-immunoractive perikarya were observed in the periventricular arcuate region in colchicine-pretreated animals. We conclude that GH-regulating neurons do not have strong reciprocal innervation. The innervation of GRF neurons by somatostatin fibres may be derived from local somatostatin neurons.
采用针对含生长激素（GH）释放因子（GRF）或生长抑素的神经元的联合免疫组织化学标记法，以及将单标记免疫组织化学与荧光金逆行转运标记相结合的方法，来研究生长抑素或GRF神经元是否可能存在相互支配关系。发现室周视前区偶尔出现的生长抑素免疫反应性神经元会被GRF免疫反应性纤维紧密靠近，这为GRF细胞对生长抑素神经元的少量支配提供了可能的证据。相反，弓状核中许多GRF免疫反应性神经元似乎有生长抑素免疫反应性纤维紧密贴附于其核周体，提示GRF神经元可能受生长抑素细胞支配。联合逆行追踪和荧光免疫组织化学显示，在下丘脑底部注射荧光金后，很少有生长抑素免疫反应性神经元出现双重标记。在视前区/前下丘脑区（PO/AHA）注射荧光金后，下丘脑底部偶尔出现的GRF免疫反应性神经元出现双重标记。在秋水仙碱预处理的动物中，在室周弓状区域观察到大量生长抑素免疫反应性核周体。我们得出结论，生长激素调节神经元不存在强烈的相互支配关系。生长抑素纤维对GRF神经元的支配可能源自局部生长抑素神经元。
