Structure-function analyses of brain angiotensin control of pressor action in rats.
Structure-function analyses of brain angiotensin control of pressor action in rats.
复制标题
大鼠脑血管紧张素控制升压作用的结构功能分析。
DOI：
10.1152/ajpregu.1989.257.6.r1551
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Harding,JW
中科院分区：
文献类型：
--
作者：
Wright,JW;Jensen,LL;Roberts,KA;Sardinia,MF;Harding,JW
The present investigation examined the relative pressor potencies of intracerebroventricularly infused angiotensin (ANG) II, successively shortened COOH-terminal fragments through ANG II(5-8), and the analogues [Sar1]ANG II through [Sar1]ANG II(5-8). The results indicate that ANG II, ANG III, [Sar1]ANG II, and [Sar1]ANG III were identical with respect to pressor responses in the alert free-moving rat. In addition, ANG II(3-8) and [Sar1]ANG II(3-8) exhibited 68-70% of the activity of the above compounds, whereas the activity of the shorter COOH-terminal fragments dropped to approximately 13-35%. Pressor responses caused by each of the active forms of angiotensin could be substantially reduced by pretreatment with the specific angiotensin receptor antagonist [Sar1,Thr8]ANG II (Sarthran), suggesting either that these ligands are acting at multiple receptors for ANG II and its fragments, which are all blocked by Sarthran, or that the ligands are acting at a common receptor site. These results, coupled with other recent findings, suggest that the brain angiotensin receptor may be designed to preferentially interact with ANG II and/or ANG III or other angiotensin analogues that structurally resemble ANG III such as [Sar1]ANG II. It is concluded that ANG III's importance as a centrally active ligand has been underestimated and that ANG III may be an active form of angiotensin in the brain.
