Inhibition of pentylenetetrazol-induced convulsions in rats by prostaglandin E1: role of brain monoamines.

Prostaglandin E1-(PGE1-) induced inhibition of pentylenetetrazol (PTZ) convulsions in rats were significantly antagonized after pretreatment with drugs known to reduce brain serotonin activity, but not by pharmacological agents that decrease brain catecholamine activity. PGF2alpha also significantly inhibited PGE1 action. The results suggest that PGE1-induced inhibition of PTZ convulsions is not a direct effect, but an indirect one mediated through increase in brain serotonin activity.