Inhibition of firing is the primary effect of microelectrophoresis phoresis of cortisol to units in th rat tuberal hypothalamus

摘要: Abstract The effects of microelectrophoresis cortisol on the firing single cells in tuberal hypothalamus rat were studied with aid multibarrel microelectrodes. It should be noted that electrodes used particularly fine (1–2 μm overall diameter) allowing close approach to without damaging them, as well permitting use small driving currents obtain reported effects. Both spontaneously active and ‘silent’ units activated by glutamate investigated. Approximately half reacted application hormone, more than 80% responsive showed reduction rate firing. Units slower spontaneous rates liable respond those faster show an inhibitory response. ‘Fast’ dorsally located non-responsive slow either cortisol-inhibited or -accelerated cells. direction response did not depend adjusted background These results dependent presence microelectrode nor chloride succinate ions mimic cortisol. literature dealing glucocorticoids cell activity is summarized it suggested demonstrated electrophysiological findings may related negative feedback at hypothalamic level exerted regulation ACTH secretion.