Genetic variation in diuretic responses: further and correlated responses to selection

Abstract

Three parameters of diuretic response to water-load (diuretic lag, maximum rate of diuresis and ratio of total output to input volume) have each responded to selection from a genetically heterogeneous base stock with significant realized heritabilities. Selection has been continued for ten generations and has produced mice more extreme than any of the founder strains. In the selection lines for ratio of output to input, correlated responses in salt excretion during the course of the diuresis, relative adrenal weight, the relative size of the renal medulla, and the quantity of renal collecting ducts, have been observed. These correlated responses are accounted for in terms of renal and adrenal physiology. The elucidation of the individual genetic determinants of the responses is discussed.