SummaryThe isoproterenol-induced diuresis in turkeys is associated with an increase in CCr and CH2O. The effect is probably mediated, in part, by β-adrenergic receptors in the afferent arteriole which lead either to recruitment of reptilian-type nephrons or more filtration by individual neph-rons. In other respects the effects of isopro-terenol in turkeys resembles those known to occur in mammals.