Nitric oxide-mediated vasorelaxation effects of anti-angiotensin I-converting enzyme (ACE) peptide from Styela clava flesh tissue and its anti-hypertensive effect in spontaneously hypertensive rats

► Vasorelaxation effect of a peptide purified from Styela clava flesh tissue was reported. ► The amino acid sequence of the peptide is Ala-His-Ile-Ile-Ile. ► It induced NO production via activation of endothelial nitric oxide synthase (eNOS). ► The peptide significantly reduced the systolic blood pressure in spontaneously hypertensive rats.