IN-VIVO FLUORESCENCE MICROSCOPY OF MICROCIRCULATION IN THE RENAL-CORTEX OF MICE .4. EFFECTS OF MANNITOL AND IOHEXOL INFUSIONS AFTER TEMPORARY RENAL ISCHEMIA

In vivo fluorescence microscopy was used for experimental studies of t he renal cortical microcirculation in mice. The effects of i.v. infusi ons of mannitol and iohexol were studied in untreated mice as well as in mice after temporary renal ischemia. All infusions produced marked effects on the distribution and velocity of cortical blood flow with n o differences between iohexol and mannitol. The renal cortical blood f low was inhomogeneous with respect to different capillaries and there was an initial rise in the number of capillaries with increased blood flow after infusions of both mannitol and iohexol. There was an initia l increase in the number of capillaries with a decreased blood flow fo llowing 30 min of ischemia. This increase was reduced by both types of infusions, suggesting a beneficial effect on renal cortical blood flo w. Neither mannitol nor contrast medium exhibited any adverse effects in ischemic kidneys that would be likely to affect renal function. How ever, 5 min after the infusions there was an increasing number of capi llaries with decreased blood flow in all groups.