Failure of dopexamine to protect the hypoxemic newborn rabbit kidney.

The renal effects of dopexamine, a new dopaminergic agonist devoid of any alpha-adrenergic effect, were studied in 11 anesthetized newborn rabbits undergoing an acute hypoxemic normocapnic stress. Acute hypoxemia (PaO2 = 41 mm Hg) was associated with a marked increase in renal vascular resistance and a consequent decrease in glomerular filtration rate and renal blood flow. These changes were not modified by the administration of dopexamine at 10 micrograms/kg/min. Failure of dopexamine to blunt the hypoxemia-induced vaso-constriction suggests vascular dopaminergic receptor immaturity.