Effects of Prostaglandin E2 and Prostaglandin F2α Upon Urinary Kallikrein Excretion in Rats

Abstract

1. In normally hydrated rats prostaglandin F,, (PGF,,) in doses of 5 pg/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, PGF,, produced similar changes in kallikrein activity and electrolyte excretion.2. In normally hydrated rats prostaglandin E, (PGEJ 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. PGE, in doses of 5, 12.5 and 25 pg/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. PGF,,, 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 PGE, and PGF,, may be part of a regulatory mechanism associated with the kallikrein-kinin system which contributes maintainance of extracellular fluid homeostasis.

Synthese und Wirkungen von Prostaglandinen in der Niere

“…4). A variety of factors beside ADH are related to renal PGE 2 formation (NaC1 [11,51] and KC1 [16,53] balance, adreno-cortical hormones [63] and bradykinin [9]. These factors could, therefore, contribute to the renal response to ADH.…”