van Vulpen E H, Yang C R, Nissen R, Renaud L P
Neuroscience Unit, Loeb Research Institute, Ottawa Civic Hospital and University of Ottawa, Ontario, Canada.
Neuroscience. 1999;93(2):675-80. doi: 10.1016/s0306-4522(99)00173-6.
This study investigated the origin of a dopaminergic innervation of the hypothalamic supraoptic nucleus. In pentobarbital-anaesthetized male Long-Evans rats, a transpharyngeal approach was used to inject a retrograde tracer, rhodamine latex microspheres, into the supraoptic nucleus. After 13-26 h survival under anaesthesia, animals were perfused transcardially, the brain sectioned and processed for tyrosine hydroxylase immunofluorescence, a marker for hypothalamic dopaminergic neurons. In six cases with injections restricted to the supraoptic nucleus, rhodamine-labelled microspheres were observed in a population of tyrosine hydroxylase-positive neurons located in the A15 cells below the anterior commissure (A15 dorsal) and above the optic chiasm (A15 ventral), and the dorsal and lateral periventricular A14 cell group. Occasional double-labelled cells were seen in the medial and lateral hypothalamus and bed nucleus of the stria terminalis, but rarely in other known dopaminergic cell groups, notably the ventral tegmental area (A10), zona incerta (A13) and substantia nigra. In support of a role for dopamine in neurohypophysial regulation, these observations indicate that the major dopaminergic input to magnocellular neurons in the hypothalamic supraoptic nucleus is derived from a relatively sparse population of neurons located in the A14 and A15 cell groups.
本研究调查了下丘脑视上核多巴胺能神经支配的起源。在戊巴比妥麻醉的雄性Long-Evans大鼠中，采用经咽入路将逆行示踪剂罗丹明乳胶微球注入视上核。在麻醉下存活13 - 26小时后，经心脏灌注动物，将脑切片并进行酪氨酸羟化酶免疫荧光处理，酪氨酸羟化酶是下丘脑多巴胺能神经元的标志物。在6例注射局限于视上核的病例中，在位于前连合下方（A15背侧）和视交叉上方（A15腹侧）的A15细胞群以及背侧和外侧室周A14细胞群中的一群酪氨酸羟化酶阳性神经元中观察到罗丹明标记的微球。在内侧和外侧下丘脑以及终纹床核中偶尔可见双标记细胞，但在其他已知的多巴胺能细胞群中很少见，特别是腹侧被盖区（A10）、未定带（A13）和黑质。为支持多巴胺在神经垂体调节中的作用，这些观察结果表明，下丘脑视上核大细胞神经元的主要多巴胺能输入源自位于A14和A15细胞群中相对稀疏的神经元群体。
