Normal renocortical blood flow in experimental acute renal failure

Normal renocortical blood flow in experimental acute renal failure. Renal cortical blood flow of rats with postischemic, myohemoglobinuric, and mercury-induced acute renal failure was measured by the hydrogen washout technique using implanted platinum electrodes. Total renal blood flow was determined by venous cannulation in separate series of rats. The values obtained with the two methods were in excellent qualitative agreement (r = 0.99, P < 0.001), although venous cannulation gave values that were constantly lower than those calculated for whole kidney from the cortical flow rate and assumed cortical mass. Myohemoglobinuria produced by glycerol injection caused cortical blood flow to fall from a control value of 7.37 ± 0.23 (SEM) ml/min × g of cortex to approximately one-half that value for four hours after injection (P < 0.001). Flow rates 12 and 24hr after glycerol injection were 85% (P < 0.001) and 90% (P < 0.05) of control, respectively. Cortical flow was reduced to 5.49 ± 0.39 (SEM) ml/min × g of cortex four hours after release of one hour's total bilateral renal arterial occlusion (P < 0.001), but rose to normal within 24hr. Poisoning with 4.7 mg/kg of body wt of mercuric chloride produced a cortical blood flow value that was 30% higher than control 24hr after injection (P < 0.01), while a 12 mg/kg of body wt dose gave a normal flow value. Inulin clearance was severely depressed in all models at all study times. Thus, in contrast to human acute renal failure, marked renal cortical ischemia is not an essential feature of these different forms of murine acute renal failure. Débit sanguin rénal cortical normal au cours de l'insuffisance rénale aiguë expérimentale. Le débit sanguin rénal cortical de rats atteints d'insuffisances rénales aiguës expérimentales post ischémique, myoglobinurique ou induite par le mercure a été mesuré par la technique du “washout” de l'hydrogène à l'aide d'électrodes de platine implantées. Le débit sanguin rénal total a été déterminé par canulation veineuse dans des groupes de rats distincts. Les valeurs obtenues par les deux méthodes montrent un excellent accord qualitatif (r = 0,99; P < 0,001) bien que les valeurs obtenues par canulation veineuse sont toujours inférieures à celles calculées, pour le rein entier, à partir du débit cortical et de la masse rénale présumée. La myoglobunurie produite par l'injection de glycérol détermine une diminution du débit sanguin cortical d'une valeur contrôle de 7,37 ± 0,23 (SEM) ml/min