Non genomic action of progesterone in rat aorta: role of nitric oxide and prostaglandins

SELLÉS J,; POLINI NÉLIDA,; ALVAREZ CRISTINA,; MASSHEIMER, VIRGINIA LAURA

Cellular Signaling

Año: 2002 vol. 14 p. 431 - 436

The mechanism of action of progesterone on rat vascular tissue was investigated. We obtained evidence that 10 nM progesterone inhibited platelet aggregation at 1-5 min. Previously we reported that NO mediated this antiaggregatory effect. RAS NOS activity in response to "in vitro” treatment with other sex steroids hormones was measured. The stimulatory action of progesterone on NO production was specific for ovarian hormones and depends on sex. The effect was non-genomic since cycloheximide did not suppress the increment in NO induced by progesterone. Finally we demonstrated that progesterone (5 min.) increase prostaclyclin release (42 – 182% above control) in a dose dependent manner (1- 100 nM). Indeed indomethacin (10 mM) completely suppressed the increment in citrulline levels induced by the hormone. These results suggest that progesterone exerts a direct non-genomic action on rat aortic metabolism, which involves NOS and COX activation and a cross talk between NO and PGI2 dependent pathways.