The study was devised to establish the role of prostaglandin E2, prostaglandin1 alpha and thromboxane A2 in the genesis of glomerular hyperfiltration response to a meat meal in healthy humans. To this end, a group of 8 healthy women was studied 4 times: in the control state (study 1), after a meat meal (study 2), following a meat meal associated with intravenous aspirin (study 3) and finally after a meat meal associated with intravenous aspirin following 2-day pretreatment with oral aspirin (study 4). Urinary excretion of prostaglandins and thromboxane increased during the glomerular hyperfiltration response to a meat meal and was suppressed by aspirin administration which did not suppress the renal hemodynamic response to the meat meal. The data do not support a causal role for prostaglandins and thromboxane A2 in the hemodynamic response to acute protein loading.