In very low concentrations, Prostaglandin E2 affects the electrical and contractile
activity of the smooth muscles of the gastric antrum, and this leads to a decrease
in the potential polarization of the membrane, and the appearance of muscle
cont
ractions. Both calcium and sodium ions play an important role in the
mechanism of the effect of prostaglandin E2 on this activity.
The smooth muscles of gastric fundus do not show any spontaneous activity.
Experiments have shown that prostaglandin E2 leads to the inhibition of the
contraction produced by stimulation, but has the opposite effect on the gastric
antrum. Calcium ions play an important role in this activity.
