TRH in therapeutic vs. nontherapeutic seizures: Affective and motor functions

We have modeled some aspects of electroconvulsive therapy (ECT) in rats. In addition to sham-treated controls, one group received two electroconvulsiv e (ECS) current-doses at grand mal seizure threshold. Two more groups recei ved three additional ECSs at two higher current-doses. Only the two suprath reshold groups showed significant antidepressant (AD) effects in the forced -swim test, but all three seizure groups showed significant increases in TR H and related peptides in anterior cortex (AC), pyriform cortex (PYR), amyg dala/entorhinal cortex (AY), and hippocampus (HC). In motor cortex (MC), TR H appeared to be increased only in the lower dose suprathreshold ECS condit ion. No condition increased TRH in striatum (STR). These results fell short of directly implicating limbic TRH in AD effects, but in HC, MC, and STR, correlations of peptide levels with individual swim scores raise the possib ility that this peptidergic system might be involved in motor as well as af fective functions. Other peptides related to TRH might also be implicated i n affective regulation and antidepressant effects. (C) 1999 Elsevier Scienc e Inc.