The effect of a meal of meat on glomerular filtration rate in dogs at normal urine flows.

1. The exogenous creatinine clearance of conscious dogs has been measured by a method in which no loading doses of water or saline were given. The urine volume was thus in the normal range, 0-1-0-3ml./min. 2. Under these conditions, the exogenous creatine clearance of fourteen dogs, measured 17 hr after a meal, was 2-74 ml./min kg-1+/-0-54 (s.d.). This is about 40% lower than values usually regarded as "normal." 3. A meal of meat, 10g/kg, increased exogenous creatinine clearance reflects an increase in glomerular filtration rate. Since this occurs with small doses of meat, increase in glomerular filtration may be important in normal renal function of dogs.