Biochemistry of the RAS

Abstract

Renal renin activity, which is demonstrated by ANG I production after incubation of kidney extract with homologous plasma under inhibition of converting enzyme activity, has been detected in selected species of all classes of vertebrates thus far examined (Henderson et al. 1981). Thus, it has become increasingly convincing that the RAS is an old hormonal system that first appeared in the most primitive jawless fish. More recently, [Asp¹, Ile⁵] ANG II-amide was isolated from the brain of a leech, Erpobdella octoculata, which exhibited a potent diuretic effect in this species (Salzet et al. 1995). Furthermore, non-amidated ANG II and an ANG I-like molecule were identified in another leech, Theromyzon tessulantus (Laurent et al. 1995).