renin Physiol.
(ˈriːnɪn)
[f. L. rēnes kidneys + -in1.]
† 1. A substance extracted from animals' kidneys and used in medicine. Obs.
| 1894 G. M. Gould Illustr. Dict. Med., Biol. & Allied Sci. 940/2 Extracts have been prepared from nearly every organ in the animal body;..cerebrin, from the brain,..ossin, from bones, renin, from the kidneys. 1900 Dorland Med. Dict. 565/1 Renin, a therapeutic extract prepared from the kidneys of animals. |
2. A proteolytic enzyme secreted by and stored in the kidneys, which acts in the blood to convert angiotensinogen (hypertensinogen) to angiotensin (hypertensin). [Coined in this sense as G. renin (R. Tigerstedt, in Compt. Rend. 12me Congrès Internat. de Médecine 1897 (1899) II. ii. 29).]
| 1906 Lancet 19 May 1375/2 The pressor substance, to which these workers give the name ‘renin’, is not dialysable. 1938 Proc. Soc. Exper. Biol. & Med. XXXIX. 214 Undialyzed renin (0·2 cc) caused moderate vasoconstriction. Ibid. 215 Renin is an enzyme-like substance which is activated by a kinase-like material contained in the protein fraction of plasma and whole blood. 1959 [see hypertensin]. 1965 [see hypertensinogen]. 1968 Passmore & Robson Compan. Med. Stud. I. xxxiii. 20/2 Renin is an enzyme which on reaching the blood activates an α2-globulin called angiotensin formed in the liver, making angiotensin I, a polypeptide containing ten amino acids. Another enzyme converts angiotensin I to angiotensin II by removing two amino acids. This last substance is the most potent pressor agent known. 1977 Freeman & Davis in J. Genest et al. Hypertension vi. 211/1 Renin is synthesized and stored..in the granules of JG [sc. juxtaglomerular] cells which are located primarily in the renal afferent arteriole, although these granular cells have also been identified in the efferent arteriolar wall..and in the mesangial cells. |