The present work was performed on uninephrectomized rabbits recovering from ischemic acute renal failure (ARF) in an attempt to elucidate whether or not intraglomerular events are a determinant factor in the development of resistance to ARF. 14 days after a 2-hour clamping of the renal artery (the recovery phase), the animals did not show resistance to an additional ischemia. On the other hand, glomeruli derived from normal kidneys displayed a contractile response to angiotensin II, arginine vasopressin or norepinephrine in Eagle's minimum essential medium, whereas glomeruli from rabbits recovering from ischemic ARF were refractory to the vasoconstrictor agents. The findings suggest that glomerular refractoriness to contractile stimuli does not provide resistance to an additional renal ischemia in the ischemic model of ARF.