DOES THE ADMINISTRATION OF SYSTEMIC RADIOGRAPHIC CONTRAST-MEDIA INFLUENCE THE ACUTE CHANGES IN RENAL PHYSIOLOGY FOLLOWING EXPOSURE TO EXTRACORPOREAL SHOCK-WAVES IN DOGS

Five anesthetized dogs were studied for 4 to 5 hours after administrat ion of extracorporeal shock waves to one kidney, the contralateral org an serving as control. Repetitive major doses of the nonionic monomeri c radiographic contrast medium (CM) iohexol were injected intravascula rly before and after application of the extracorporeal shock waves for further provocation of kidney function. Urinary excretion of electrol ytes, N-acetyl-beta-glucosaminidase (NAG) and kallikrein, clearances o f creatinine, inulin and para-amino-hippuric acid (PAH), serum aldoste rone level and plasma renin activity (PRA) were determined. On the exp osed side there was a significant fall in urinary osmolality. Effectiv e renal plasma flow (ERPF) was reduced and glomerular filtration rate (GFR) was unchanged; thus filtration fraction (FF) was increased. Extr action of PAH was reduced, and true renal plasma flow was unchanged. U rinary osmolality on the control side was unchanged. There was a fall in ERPF and increased GFR; therefore, FF increased. The mean rise of P RA in the exposed kidney was significant after shock waves. Urine volu me and urinary excretion of electrolytes and kallikrein were stable bi laterally. Relating the results to those obtained in identical canine experiments without CM, simultaneous administration of CM does not see m to significantly influence the changes in kidney function parameters caused by extracorporeal shock waves in the dog.