Study of renal functions by repeated constant infusion of radiotracers before and after initiation of therapy in hypertension or in diabetes mellitus.
Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were simultaneously measured by obtaining an isotopic steady state during a continuous infusion of 125I orthoiodohippurate (OIHA). A good correlation was found between the clearances of Ioth (y) and of inulin or polyfructosan (x) : y = 1.18 X (x) + 8.43 (r = 0.96; P less than 0.001) and between the clearances of OIHA (y') and of PAH (x') : y' = 0.62 X (x') + 21.2 (r = 0.93; P less than 0.001). When renal functions were impaired the use of Ioth was not convenient since the infusion time necessary to reach a radioactive plateau was longer than 3 hours. On the contrary, excellent results were obtained by using OIHA. In this case, the main advantages were the absence of urine collection and the rapid obtention of an isotopic equilibrium. The repeated determination of renal clearances in hypertensive or diabetic patients appears to be useful in the study of changes induced by antihypertensive drugs or insulin. Clearances were slightly improved by clonidine, claimed to be useful in hypertension associated with chronic renal failure. GFR and ERPF were rapidly increased by insure on the metabolic and hemodynamic changes induced by insulin than on the return to normal of glomerular basement membrane permeability.
D000317:Adrenergic alpha-Antagonists / Q000627:therapeutic use; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D003000:Clonidine / Q000627:therapeutic use; D003920:Diabetes Mellitus / Q000188:drug therapy*; D003981:Diazoxide / Q000627:therapeutic use; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D007328:Insulin / Q000627:therapeutic use*; D007444:Inulin; D007457:Iodine Radioisotopes; D007465:Iodohippuric Acid; D007483:Iothalamic Acid; D007668:Kidney / Q000098:blood supply / Q000503:physiopathology*; D007677:Kidney Function Tests; D007678:Kidney Glomerulus / Q000503:physiopathology
D000317:Adrenergic alpha-Antagonists; D000959:Antihypertensive Agents; D007328:Insulin; D007457:Iodine Radioisotopes; D007465:Iodohippuric Acid; D007483:Iothalamic Acid; D007444:Inulin; D003000:Clonidine; D003981:Diazoxide