Angiotensin II binding sites in the hamster brain: localization and subtype distribution.
Angiotensin II binding sites in the hamster brain: localization and subtype distribution.
复制标题
仓鼠大脑中血管紧张素 II 结合位点：定位和亚型分布。
DOI：
10.1016/0006-8993(92)91457-p
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发表时间：
1992
期刊：
影响因子：
2.9
通讯作者：
Rowe,BP
中科院分区：
文献类型：
--
作者：
Saylor,DL;Perez,RA;Absher,DR;Baisden,RH;Woodruff,ML;Joyner,WL;Rowe,BP
本研究旨在表征仓鼠大脑中血管紧张素 II (AII) 结合位点的分布。在血管紧张素 II 受体亚型选择性化合物氯沙坦（AAT，亚型）和 PD123177（AT2 亚型）不存在和存在的情况下，将脑切片与 [125I][sar1, ile8]-血管紧张素 II 一起孵育。通过光密度放射自显影图对结合进行量化，并通过与相邻的硫堇染色切片进行比较来定位结合。 AII 结合位点的分布与大鼠中发现的相似，但有一些例外。 [125I][sar1, ile8]-血管紧张素 II 结合在仓鼠的丘脑底核和丘脑区域、下橄榄核、视交叉上核和梨状皮层（大鼠脑中的显着结合区域）中不明显。然而，在仓鼠的脚间核和内侧缰核中观察到强烈的结合，而在大鼠脑中则没有结合的核。与受体亚型选择性化合物的竞争揭示了两个物种的大脑区域中相似的 AII 受体亚型特征，其中结合是明显的。一个值得注意的例外是内侧膝状核，在仓鼠中主要是 AT1 结合位点，但在大鼠中主要是 AT2 结合位点。一般来说，仓鼠大脑中 AII 结合位点的分布与所研究的其他物种的分布相似，特别是在与心血管和动力功能相关的大脑区域。大多数大脑区域中 AII 结合位点的功能相关性尚未阐明，物种不匹配可能提供这方面的线索。
This study was designed to characterize the distribution of angiotensin II (AII) binding sites in the hamster brain. Brain sections were incubated with [125I][sar1, ile8]-angiotensin II in the absence and presence of angiotensin II receptor subtype selective compounds, losartan (AAT, subtype) and PD123177 (AT2subtype). Binding was quantified by densoritometric autoradiograms and localized by comparison with adjacent thionin stained sections. The distribution of AII binding sites was similar to that found in the rat, with some exceptions. [125I][sar1, ile8]-angiotensin II binding was not evident in the subthalamic nucleus and thalamic regions, inferior olive, suprachiasmatic nucleus, and piriform cortex of the hamster, regions of prominent binding in the rat brain. However, intense binding was observed in the interpeduncular nucleus and the medial habenula of the hamster, nuclei void of binding in the rat brain. Competition with receptor subtype selective compounds revealed a similar AII receptor subtype profile in brain regions where binding is evident in both species. One notable exception is the medial geniculate nucleus, predominately AT1binding sites in the hamster but AT2in the rat. Generally, the AII binding site distribution in the hamster brain parallels that of the other species studied, particularly in brain regions associated with cardiovascular and dipsogenic functions. Functional correlates for AII binding sites have not been elucidated in the majority of brain regions and species mismatches might provide clues in this regard.