Influence of PGF2 alpha on gastrointestinal activity in the conscious piglet.

In 5 conscious piglets with electrodes implanted on the antrum pylori, duodenum, jejunum and ileum, the effect of intravenous infusion of PGF2 alpha, 1 and 10 micrograms/kg/min during 2 h, on gastrointestinal electrical activity was studied. The influence of the PG, 10(-8) to 10(-4) M, on longitudinal tissue strips from the same segments was also examined. The in vitro results demonstrate that PGF2 alpha has only a weak contractile effect on duodenal and jejunal strips. This effect was enhanced in the presence of atropine and indomethacin. In the in vivo part of the study PGF2 alpha induced an inhibition of antral electrical activity as evidenced by a prolongation of the inhibitory phases and a reduction of the frequency of the fast oscillations. In the small intestine only ileal activity was changed significantly. PGF2 alpha provoked an increase in the phase II or irregular spiking activity and an increase in the interval of the migrating myoelectrical complexes in this segment.