[Characteristics of the response of the white rami communicantes to stimulation of different sections of the amygdaloid body].

Electrical responses in L2-L3 white rami to stimulation of cortico-medial, baso-lateral and central amygdaloid nuclei were studied in anesthetized and immobilized cats. The stimulation evoked a similar pattern of sympathetic discharge mostly consisting of a wave with a mean latency of 69.04 +/- 1.31 ms. No strict topographical location of sympatho-activating structures was found in different areas of the amygdala. In simultaneous recording of arterial BP and amygdalo-sympathetic discharges, 10-sec period of tetanic (100/sec) stimulation of the amygdalo led to a short-latency component facilitation or appearance, the late component of the amygdalo-sympathetic discharge being depressed. The duration of the latter inhibition corresponded to the period of the BP reaction and therefore was of a baroreceptor origin. Possible mechanisms of amygdaloid regulation of the activity of sympathetic preganglionic neurons are discussed.