Effects of captopril on urinary excretion of prostaglandins and electrolytes in spontaneously hypertensive rats.
Captopril was administered to spontaneously hypertensive rats (SHR) and the acute and long-term effects on the urinary excretion of Na, K, prostaglandin (PG)E2 and PGF2 alpha were studied. Captopril (30 mg and 100 mg/kg p.o.) increased urine volume, urinary Na and K excretion on the 1st and 2nd days of its administration. The urinary K/Na ratio was decreased in the captopril-treated groups on the 1st to 3rd day. Urinary PGE2 excretion in the captopril 100 mg/kg group was significantly increased compared to that in the control group (210.6 +/- 31.4 vs. control 123.2 +/- 8.4 ng/day) on the 1st day of captopril administration. A slight but significant increase in urinary PGF2 alpha excretion was also seen in the captopril 100 mg/kg group (105.2 +/- 9.8 vs. control 75.8 +/- 2.1 ng/day). But PG excretion declined during prolonged treatment and these were no significant difference between the control and captopril-treated groups on the 3rd and 6th week. These data suggest that captopril increases renal PG only as an acute phase and that the increase of PG at least partly accounts for natriuretic affects of the agent.
D000818:Animals; D002216:Captopril / Q000494:pharmacology*; D004573:Electrolytes / Q000652:urine*; D006973:Hypertension / Q000652:urine*; D008297:Male; D011188:Potassium / Q000652:urine; D011392:Proline / Q000031:analogs & derivatives*; D011453:Prostaglandins / Q000652:urine*; D011458:Prostaglandins E / Q000652:urine; D011460:Prostaglandins F / Q000652:urine; D051381:Rats; D011919:Rats, Inbred Strains; D012083:Renin / Q000097:blood; D012964:Sodium / Q000652:urine
D004573:Electrolytes; D011453:Prostaglandins; D011458:Prostaglandins E; D011460:Prostaglandins F; D011392:Proline; D002216:Captopril; D012964:Sodium; D012083:Renin; D011188:Potassium