Effects of prostaglandin E2 and prostaglandin F2alpha upon urinary kallikrein excretion in rats.
1. In normally hydrated rats prostaglandin F2alpha (PGF2alpha) in doses of 5 microgram/100 g body weight given subcutaneously every 2 h (three times) induced a significant increase in urinary kallikrein activity, and in sodium, potassium and water excretion for 8 h after the first injection. In moderately hyperhydrated rats loaded 2.5% of body wt. with 0.5% NaCl solution, PGF2alpha produced similar changes in kallikrein activity and electrolyte excretion. 2. In normally hydrated rats prostaglandin E2 (PGE2) in the same conditions and doses as in 1 had no effect on kallikrein activity, showing a tendency to decrease potassium and water excretion. 3. PGE2 in doses of 5, 12.5 and 25 microgram/100 g body wt. in overhydrated rats given 2.5% and 0.5% NaCl and 5% of tap water/100 g body wt. 1 h later, significantly increased kallikrein activity in the urine collected for 120 min after the injections. A significant decrease in potassium and water excretion was observed with the highest dose. 4. PGF2alpha, had no effect on kallikrein activity in overhydrated rats, but an increase in sodium and a decrease in potassium excretion was seen at the highest dose. 5. The different actions of PGE2 and PGF2alpha may be part of a regulatory mechanism associated with the kallikrein-kinin system which contributes maintainance of extracellular fluid homeostasis.
D000818:Animals; D001834:Body Water / Q000378:metabolism; D004231:Diuresis / Q000187:drug effects; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D007610:Kallikreins / Q000652:urine*; D011458:Prostaglandins E / Q000494:pharmacology*; D011460:Prostaglandins F / Q000494:pharmacology*; D051381:Rats; D014882:Water-Electrolyte Balance / Q000187:drug effects*
D011458:Prostaglandins E; D011460:Prostaglandins F; D007610:Kallikreins