BIOCONVERSION OF ARACHIDONIC-ACID IN HUMAN PREGNANT UTERINE CERVIX

The in vitro conversion of [14C]arachidonic acid by endocervical mucosa and cervical tissue specimens obtained in 1st trimester (9-12 wk) and term pregnant patients (37-39 wk) was studied in whole-cell homogenates. All radiolabeled products of the arachidonic acid cascade were extracted, purified and separated utilizing silicic acid chromatography, thin-layer chromatography and reversed phase partition chromatography and identified with radio-gas chromatography and gas chromatography-mass spectometry. Both types of tissue produced PG [prostaglandin]F2.alpha. and PGE2, as well as TxB2. In cervical tissue specimens there was a significant increase in the production of all these 3 prostaglandins as the pregnancy progressed, whereas no such difference was seen in homogenates of endocervical mucosa. In both endocervical mucosa and cervical tissue specimens there was a highly significant increase in the production of a so-far unknown compound(s), in samples from term patients as compared with samples from 1st-trimester patients. The possible participation of this metabolite of [14C]arachidonic acid in the regulation of cervical ripening is discussed.