THE EFFECT OF VASOPRESSIN V1-RECEPTOR AND V2-RECEPTOR ANTAGONISTS ON HEMODYNAMICS IN EARLY AND LATE-PHASE AFTER MYOCARDIAL-INFARCTION IN RATS

This study was designed to assess the effect of a nonpeptide vasopress in V1-receptor antagonist, OPC-21268, and a vasopressin V2-receptor an tagonist, OPC-31260, on hemodynamics in the early phase and the late p hase after myocardial infarction in rats. In the early phase, OPC-2126 8 (30 mg/kg/day) or OPC-31260 (30 mg/kg/day) was orally administered f rom day 1 to day 5 after the operation; and hemodynamics were measured at day 5, in the late phase from 10 weeks to 11 weeks and measured at the end of 11 weeks. In the early phase, OPC-21268 reduced the left v entricular end-diastolic pressure (LVEDP) concomitantly with the reduc tion in systemic blood pressure, but did not change LVEDP in the late phase. OPC-31260 reduced LVEDP and central venous pressure in both pha ses. OPC-21268 improved hemodynamics only in the early phase and OPC-3 1260 improved it in both phases.