Evidence for oscillation of prostaglandin release from spontaneously contracting guinea pig taenia coli.

Two strips of guinea pig taenia coli were mounted 1-2 mm apart in a small organ bath. One of the strips was incubated before mounting with indomethacin, which inhibited release of prostaglandin E2 for at least 4 h to levels not detectable by biological assay. Both stretch-evoked contractions or spontaneous contractions of the prostaglandin-releasing strip reduced the contraction time intervals between spontaneous contractions in the paired strip. Neither stretch-evoked nor spontaneous contractions of the nonprostaglandin-releasing strip influenced spontaneous contractions in the paired strip. With the strips widely separated, stretch-evoked contractions of the prostaglandin-releasing strips caused shortened contraction-time intervals in the paired strips, but spontaneous contractions had no such effect. Rat fundus, separated 1-2 mm from prostaglandin-releasing taenia coli, showed small contractions occurring at the same frequency as spontaneous taenia contractions. These rat fundus contractions were abolished by indomethacin. Data show that there is communication between the prostaglandin-releasing strip and the nonprogestaglandin-releasing strip, There is evidence that this communication was mediated by released prostaglandin E2 and that release of this mediated is augmented during spontaneous contractions of guinea pig taenia coli.