Thyrotropin releasing hormone stimulation of GABA-gated but not basal chloride ion influx in rat cerebellum

Potential interaction between gamma-amino butyric acid (GABA) and thyrotrop in-releasing hormone (TRH) in eliciting a variety of central nervous system (CNS)-related biologic activities is well known; however, the mechanism un derlying this interaction is not clearly defined. To gain further insight i nto this interaction, we examined the effects of TRH and two of its central nervous system selective analogs, DN 1417 and TA 0910, on basal and GABA-m ediated chloride ion influx into rat cerebellar neurosynaptosomes. The resu lts of these studies show that TRH may facilitate GABA action by augmenting chloride ion influx and hyperpolarization of cerebellar neurons. (C) 1999 Elsevier Science Inc. All rights reserved.