ABSTRACT
Recent progress in our understanding of the γ-aminobutyric acid (GABA) receptor complex may have implications for the analysis of fear and anxiety. Our purpose in this chapter is threefold; 1) to describe some relevant concepts about the action of substances that modulate GAB Aergic transmission focusing upon a particular ß-carboline, methyl 6,7-dimethoxy-4-ethyl-ß-carboline-3-carboxy-late (DMCM), 2) to discuss experimental evidence from our laboratory suggesting that administration of DMCM results in behavioral effects that roughly parallel those found in Pavlovian fear conditioning and 3) briefly consider the possibility that an endogenous substance functioning like DMCM is involved in normal Pavlovian fear conditioning.
