Another component of the renin-angiotensin-aldosterone system is bradykinin , a vasoactive peptide metabolized by the same enzyme that converts angiotensin I to angiotensin II.

The peptide subfamily of GPCR contains receptors that bind a disparate array of peptides, such as angiotensin, bradykinin , opioid, somatostatin, and chemokines.

The profile parallels that observed for bradykinin stimulated smooth muscle cells.

This class of receptors includes the angiotensin, bradykinin and vasopressin receptors.

Vasodilators, such as acetylcholine and bradykinin , do not exert their effects upon the vascular smooth muscle cell in the absence of the overlying endothelium.