[Baclofen inhibition of synaptic transmission in glomeruli of the olfactory bulb of the frog].

The application of (+/-) baclofen (10(-5) M) to the frog olfactory bulb greatly reduced postsynaptic components of the orthodromic potential, but the antidromic potential was not affected. The effect was not antagonized by bicuculline (10(-4)-10(-3) M). The results suggest that bicuculline-insensitive GABAB-receptors are located on the primary olfactory afferents and may realize presynaptic inhibition in the olfactory bulb.