INFLUENCE OF EPOXYEICOSATRIENOIC ACIDS ON UTERINE FUNCTION

In spite of the large quantities of epoxyeicosatrienoic acids (EEts) r eleased by reproductive tissues, their function has not yet been deter mined. In order to analyze the influence of epoxygenase products on is olated uterine function, Clotrimazole, a cytochrome P450 inhibitor was used. The drug decreased isolated rat uterine isometric developed ten sion (IDT) and frequency (FC). 14,15 EEt induced a contractile respons e when added at 10(-11) M, 8,9 EEt and 11,12 EEt produced an increment of IDT when added at 10(-7) Rn and 5,6 EEt did not modify IDT values. A contractile stimulatory effect was observed when 14,15 EEt (10(-7) M) was added to a tissue bath preparation containing Clotrimazole (20 mu M). On the other hand, uterine contractile response to 14,15 EEt ad dition was partially abolished by indomethacin (10(-6) M), a well know n cyclooxygenase inhibitor. Uterine response to 5,6;8,9 and 11,12 EEts was not modified by indomethacin. This is the first evidence of 14-15 EEt uterotonic properties, possibly exerted in part through the cyclo oxygenase pathway.