| Abstract: | The effects of subiculum stimulation were investigated in 80 antidromically identified hypothalamic supraoptic neurons in lactating rats. Inhibition manifesting as suppression of antidromic action potentials (or of their somatodendritic component) was revealed in 26% of cells, induced by applying conditioned and test stimuli to the subiculum and neurohypophysial stalk. In some instances inhibition arose following a latency of 5–25 msec after each subicular stimulus and lasted only briefly; it set in gradually in other cases, leading to stable long-term changes in the excitability of neurosecretory cells. No activation was produced by this stimulation. It is deduced that subicular inhibitory inputs follow different patterns, thus reflecting morphological organizational aspects of synaptic inhibitory inputs to neurosecretory cells.A. A. Ukhtomskii, Institute of Physiology, A. A. Zhdanov State University, Leningrad. Translated from Neirofiziologiya, Vol. 20, No. 4, pp. 431–437, July–August, 1988. |
