The effects of prostaglandins on the beating activity of cultured heart cells.

The effects on the beating behavior of cultured rat heart cells of fourteen prostaglandins of the A, B, D, E, and F series were investigated, together with adrenaline and ouabain, at dose levels of 10-7 and 10-5M. Single heart cell beating activity was monitored photo-electrically and five parameters of beating behavior measured. Only PGF2alpha markedly increased rate while PGF2beta reduced it. Maintenance of a stable rate (rate range) was minimally affected by prostaglandins with PGF2beta possibly reducing, and PGF1alpha and 2-decarboxy E1 possibly increasing, rate range. PGF1alpha and F2alpha both statistically reduced the percentage of cells beating while the other prostaglandins had no effect. Most of the prostaglandins either produced no change, or reduced, indices of contractile force (optical density changes with contractions and its first derivative (dOD/dt)). Only the negative chronotropic agent PGF2beta produced a positive density effect. In conclusion, except for PGF2alpha, prostaglandins generally have limited actions on the beating activity of cultured heart cells.