A study on the effects of inhibition of prostaglandin biosynthesis with flunixin meglumine and later administration of prostaglandin F2 alpha on the intraluminal pressure variations in the isthmus of the oviduct in unrestrained gilts.

Three gilts were each equipped with 2 ultra-miniature pressure sensors, placed at 2 different points along the same isthmus of the oviduct. Following base recordings of isthmic intraluminal pressure, the gilts were treated with 2.2 mg flunixin meglumine (FM) per kg body weight. After FM treatment, the peripheral plasma levels of 15-ketodihydro-PGF2 alpha, the major metabolite of prostaglandin F2 alpha (PGF2 alpha), decreased within 30 min. The frequency of the phasic pressure fluctuations in the isthmus of the oviduct decreased after FM treatment. Exogenous administration of PGF2 alpha increased the peripheral plasma levels of 15-ketodihydro-PGF2 alpha. When administered at a dose of 0.1 mg, PGF2 alpha produced an increase in the frequency of the phasic pressure fluctuations in the oviductal isthmus. When the PGF2 alpha dose was increased to 0.5 mg, a marked increase in the base and total pressures was seen in addition to the increase in the frequency of the phasic pressure fluctuations.