[Kidney glomerular hemodynamics in the rodent Calomys callosus]

Renal function was characterized in Calomys callosus, a rodent which can participate in the transmission of several human diseases. The results showed that the pressures levels, hematocrit and plasmatic proteins were similar to rats submitted to the same experimental maneuvers. The corporal and renal weights, whole and single nephron glomerular filtration rates were similar to the mouse. This rodent presented a significant number of superficial glomeruli, allowing to evaluate glomerular hemodynamics and renal microcirculation parameters. Despite mean arterial pressure similar to the Munich-Wistar (MW) rats, mean glomerular capillary hydraulic pressure was lower in Calomys callosus, due to a lower post glomerular resistance in this rodent when compared to MW rats. The mean glomerular plasma flow rate was relatively elevated when compared with single nephron glomerular filtration rate, which in turn blunted the lower intraglomerular hydraulic pressure, and thus increased the single nephron glomerular filtration rate per g/kidney. The present work suggests that despite of the technical difficulties imposed by the reduced size of the Calomys callosus, the study of the renal function and glomerular hemodynamics is possible, establishing therefore, a model for the study such renal function.