The etiology of renal vasoconstriction in acute pancreatitis remains obscure. The canine model of bile pancreatitis was used to determine whether hypovolemia or increased circulating levels of catecholamines are responsible for this phenomenon. Treatment of the pancreatitis was either with volume loading or alpha adrenergic blockade with Prazosin given both before and after the induction of pancreatitis. Neither pretreatment nor post-treatment with either volume loading or Prazosin protected the kidneys from the standpoint of mitigating renal vasoconstriction. To the contrary, treatment with alpha blockade produced the greatest decreases in renal blood flow.