Modulation of the proestrous surge of luteinizing hormone by electrochemical stimulation of the amygdala and hippocampus in the unanesthetized rat

摘要: Abstract The roles played by the amygdala and hippocampus in controlling release of pituitary luteinizing hormone (LH) were studied freely moving rat. Monopolar stainless steel electrodes implanted into corticomedial (CM) amygdala, basolateral (BL) dorsal female rats. When animal had recovered from surgery shown two consecutive 4-day estrous cycles, a chronic atrial cannula was introduced during afternoon diestrus II. On following day (proestrus) electrochemical stimulation (ECS) applied (20–50 μA anodal DC 120 sec) bilaterally to or blood samples taken every 90 min 12.00 21.00 h for radioimmunoassay (RIA) LH. Next day, uterine tubes examined ova as evidence ovulation. ECS exerted divergent influences on LH release. Stimulation BL at 13.45 h, just before critical period (14.00–16.00 h), effective delaying reducing surge, whereas CM resulted an early synchronization timing curves. All rats both groups ovulated, contrast results applying hippocampus; there surge ovulation completely blocked 7 out 9 Thus, rat, can exert potent inhibitory influence plays modulatory role process.