Serpin A8 (or angiotensinogen) is a key regulator of the renin-angiotensin system, affecting blood pressure, fluid and electrolyte balance.As a vasoconstrictor, it directly affects vascular smooth muscle and affects myocardial contractility and heart rate through the sympathetic nervous system.Serpin A8/Angiotensinogen Protein, Rat (HEK293, His) is the recombinant rat-derived Serpin A8/Angiotensinogen protein, expressed by HEK293 , with C-His labeled tag.