The renal hemodynamic response to diatrizoate in normal and diabetic rats.
To study the renal hemodynamic response to a large intravenous bolus of a radiocontrast agent, 8 ml/kg body weight of 60% diatrizoate meglumine (D-60) was infused over 30 seconds in both normal rats and rats with streptozotocin-induced diabetes. The effect of equiosmolar mannitol (1350 mOsm/kg) was compared with the D-60 response in normal rats to examine the potential role of hypertonicity in mediating a response. A similar two-phase response was seen in all three groups. The effect of D-60 in normal rats was similar to that of mannitol, but all responses were reduced in diabetic rats. During Phase I in normal rats in response to D-60 there was a transient three-minute reduction in blood pressure (BP), and renal blood flow (RBF) fell by 62 +/- 7%. During Phase II blood pressure did not change from normal baseline values, but RBF fell by 29 +/- 5%; GFR fell by 42 +/- 3%, and filtration fraction (FF) diminished. In diabetic rats baseline FF was lower than normal and was not further reduced after infusion of D-60. It is suggested that D-60 reduces RBF and GFR by a nonspecific osmotic effect, perhaps related to tubuloglomerular feedback or to an acute increase in intratubular pressure. Responses to these mechanisms may be reduced in diabetic rats with a chronic glycosuric osmotic diuresis.
D000818:Animals; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D003973:Diatrizoate / Q000031:analogs & derivatives*; D003974:Diatrizoate Meglumine / Q000008:administration & dosage* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D007263:Infusions, Parenteral; D008297:Male; D008353:Mannitol / Q000494:pharmacology; D009994:Osmolar Concentration; D051381:Rats; D011919:Rats, Inbred Strains; D012079:Renal Circulation / Q000187:drug effects*
D003973:Diatrizoate; D008353:Mannitol; D003974:Diatrizoate Meglumine