Effect of prostagladin F2 alpha on the bovine fetal ruminal wall in vitro

Strips of rumen wall from bovine fetuses were incubated in an organ bath with prostaglandin F₂ alpha (0.13 to 33.76 g/ml). The highest reactivity with a submaximal dose (17.03 g/ml) was observed in the period between 3.0 and 7.9 months of fetal age. A smaller response, but higher than in 1.0 to 2.9 months old fetuses, was observed in the 8.0 to 8.9 months fetuses. The period of the highest reactivity to prostaglandin F₂ alpha coincides with the age of onset of papillary morphogenesis and the period of highest reactivity to autonomic and putative transmitter drugs.