Expression of GABAB receptors in magnocellular neurosecretory cells of male, virgin female and lactating rats.
Expression of GABAB receptors in magnocellular neurosecretory cells of male, virgin female and lactating rats.
复制标题
GABAB 受体在雄性、雌性和哺乳期大鼠的大细胞神经分泌细胞中的表达。
DOI：
10.1111/j.1365-2826.2005.01324.x
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Stern,JE
中科院分区：
文献类型：
--
作者：
Richards,DS;Villalba,RM;Alvarez,FJ;Stern,JE
GABA is one of the key neurotransmitters that regulate the firing activity of neurones in the supraoptic (SON) and paraventricular (PVN) nuclei. In the present study, we used immunohistochemical techniques to study the distribution and subcellular localisation of metabotropic GABABreceptors in magnocellular neurones in the SON and PVN. Robust GABABreceptor immunoreactivity (GABABR; both subunit 1 and subunit 2 of the heterodimer), was observed in the SON and PVN. At the light microcope level, GABABR immonoreactivity displayed a clustered pattern localised both intracytoplasmically and at the plasma membrane. Densitometry analysis indicated that GABABR immunoreactivity was significantly more intense in vasopressin cells than in oxytocin cells, both in male, virgin female and lactating rats, and was denser in males than in virgin females. Light and electron microscope studies indicated that cytoplasmic GABABR was localised in various organelles, including the Golgi, early endosomes and lysosomes, suggesting the cycling of the receptor within the endocytic and trafficking pathways. Some smaller clusters at the level of the cell plasma membrane were apposed to glutamic acid decarboxylase 67 immunoreactive boutons, and appeared to be colocalised with gephyrin, a constituent protein of the postsynaptic density at inhibitory synapses. The presence of GABABR immunoreactivity at synaptic and extrasynaptic sites was supported by electron microscopy. These results provide anatomical evidence for the expression of postsynaptic GABABreceptors in magnocellular neurosecretory cells.
