Hemodynamic effects of XXXX on the @entity235 kidney.

@entity8 @entity235 @entity1372 @entity2918 @entity8303 @entity3766 @entity3352 @entity5567
@entity8303 ( @entity5567 ) is a potent vasodilator produced in several organs, including the kidney. In the present study, the effect of intra-femoral @entity5567 (0.78 micrograms/kg) in control @entity235 (Group 1) or @entity3352 (3 mg/kg) treated animals (Group 2) was examined. In Group 1, systemic blood pressure dropped from 108 +/- 8 to 47 +/- 7 mmHg following @entity5567 and hematocrit rose from 42 +/- 2 to 56 +/- 2%. These changes were associated with a reduction in both urine flow, urinary @entity1372 (from 69 +/- 9 to 25 +/- 6 muEq/min), glomerular filtration and renal plasma flow (from 28 +/- 2 to 11 +/- 1 and 52 +/- 5 to 26 +/- 4 ml/min, respectively). All parameters returned to normalcy during the following 50 minutes. In Group 2, the systemic effects of @entity5567 were abolished by @entity3352 . However, @entity3352 failed to prevent the @entity8 which were altered as in Group 1. In additional experiments (Group 3) the influence of @entity3766 , a specific antagonist of @entity5567 receptors, was examined. The dose of @entity5567 utilized in this group was 0.78 micrograms/kg, whereas @entity3766 was administered 30 minutes before @entity5567 injections in increasing doses (1.0, 2.5, 5.0 and 25.0 micrograms). This antagonist blocked the effect of @entity5567 on blood pressure and renal parameters in a dose-related manner. Finally, the effect of intrarenal @entity5567 was studied (Group 4: increasing continuous infusions of 2, 5, 10, and 20 ng/kg/min; Group 5: single bolus of 0.15 and 0.30 micrograms/kg). In these two groups, the systemic effects of @entity5567 were abolished as expected. In Group 4, a dose related reduction of urinary @entity1372 was observed during the continuous infusion of @entity5567 . Only at higher doses, was an effect on glomerular filtration and renal plasma flow observed. In Group 5, a marked reduction of urinary @entity1372 (from 110 +/- 15 to 22 +/- 5 muEq/min) occurred while glomerular filtration and renal plasma flow decreased by approximately 50%. These data support a direct influence of @entity5567 on urinary @entity1372 excretion and renal hemodynamics. The peripheral effects of this compound are mediated by vasodilatory @entity2918 , as shown in Group 2. Finally, the actions of this powerful vasodilator on the kidney do not require the intervention of systemic influences, as clearly demonstrated in Groups 4 and 5.
