DISCRIMINATIVE STIMULUS PROPERTIES OF MIDAZOLAM ARE SHARED BY A GABA-RECEPTOR POSITIVE STEROID

3-Alpha-5-alpha-tetrahydrodeoxycorticosterone (alloTHDOC) is a 3-alpha ring A-reduced metabolite of deoxycorticosterone that has been shown to act via nongenomic mechanisms to modulate the GABA(A) receptor comp lex allosterically in vitro. Moreover, there are behavioral data consi stent with the anxiolytic actions of GABA-receptor positive steroids. The drug discrimination paradigm was used in rats to demonstrate that effects of alloTHDOC are mediated by the GABA(A) receptor complex in t he intact animal. In rats trained to discriminate 1.8 mg/kg of midazol am from saline, alloTHDOC substituted for the training stimulus.