[Effect of rhythmic and tonic stimulation on the neuronal activity of the olfactory bulb in the newt Triturus cristatus].

Studies have been made of the dependence of neuronal reactions in the olfactory bulb of the newt on the pattern of presentation of a test solution (glutamine 10(-5) M) into the nasal cavity. Responses to stimulation at a frequency 6/min (which corresponds to the minimal rhythm of normal buccal movements) varied in the intensity and sign. The peak of excitation was usually observed after the 2nd or the 3rd stimuli. The increase of stimulation frequency up to 12-24/min increased the number of the inhibitory reactions and the intensity of inhibition. Replacement of rhythmic flow by a constant one results in inhibition of 34% of neurones which reacted by activation to the rhythmic series of 6/min. The data obtained are discussed in relation to the pattern of olfactory perception in newts under natural conditions.