Background:

Angiotensin I (Ang I) (C62H89N17O14), with the sequence H-Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-OH, is formed by the action of renin on angiotensinogen. Renin is produced in the kidneys in response to renal sympathetic activity, decreased intrarenal blood pressure (<90mmHg systolic blood pressure) at the juxtaglomerular cells. Ang I appears to have no biological activity and exists solely as a precursor to angiotensin II (A II). Ang I is cleaved to Ang II by the angiotensin-converting enzyme (ACE). Ang II increases blood pressure by stimulating the Gq protein in vascular smooth muscle cells (which in turn activates contraction by an IP3-dependent mechanism).

参考文献:
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