[Experimental study of effect of water deprivation-induced dehydration on renal function in rats]

To clarify the renal function induced by water deprivation-induced dehydration, intrarenal blood flow and changes in adenine nucleotide level in the renal tissue were investigated. Male SD rats were completely deprived of water for 2, 4 and 5 days. The intrarenal blood flow was determined by the hydrogen-gas clearance method and adenine nucleotide level in the renal tissue by high pressure liquid chromatography (HPLC) on the 2nd, 4th, and 5th day after water deprivation. The renal function and energy charge (EC = [ATP + 1/2 ADP]/[ATP + ADP + AMP]) were normal in all rats. In the dehydrated rats, the urine and blood were concentrated, and the medullary blood flow decreased. The mean arterial blood pressure was in the lower limit of renal perfusion pressure under autoregulation. In conclusion, the lower limit of renal perfusion pressure under autoregulation and urine and blood concentration due to water deprivation-induced dehydration may easily cause acute renal failure.