Nishioka T, Anselmo-Franci J A, Li P, Callahan M F, Morris M
Department of Physiology and Pharmacology, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157-1083, USA.
Brain Res. 1998 Jan 19;781(1-2):57-61. doi: 10.1016/s0006-8993(97)01159-1.
Evidence indicates that the hypothalamic paraventricular nucleus (PVN) and oxytocin (OT) neurons in particular play a role in the physiological response to stress. Microdialysis (MD) experiments were performed to determine whether OT is released into the PVN during shaker stress. Male rats were prepared with venous catheters and PVN guide cannulae. OT and vasopressin (VP) release into PVN and peripheral blood were measured under basal conditions and during and after shaker stress (10 min at 110 cycles/min). Stress produced a specific increase in PVN and plasma OT. Dialysate OT levels were 0.3+/-0.1, 2.8+/-1.2 and 1.3+/-0.6 pg/sample (control, stress and recovery, respectively). Plasma OT was significantly increased during stress (3.7+/-1.2 vs. 11.7+/-2.3 pg/ml, basal vs. stress, respectively). When MD probes were located outside the PVN, there was no increase in OT release, demonstrating site specificity. Stress produced no change in VP levels, either in dialysate or plasma. These results show that OT, but not VP, is released into the PVN and peripheral blood in response to shaker stress. The data raise the possibility that local release of OT into the PVN plays a role in the neuroendocrine stress cascade.
有证据表明，下丘脑室旁核（PVN）尤其是催产素（OT）神经元在对应激的生理反应中发挥作用。进行了微透析（MD）实验，以确定在摇晃应激期间OT是否释放到PVN中。给雄性大鼠植入静脉导管和PVN引导套管。在基础条件下以及摇晃应激期间和之后（110次循环/分钟，持续10分钟）测量OT和加压素（VP）释放到PVN和外周血中的情况。应激导致PVN和血浆OT特异性增加。透析液OT水平分别为0.3±0.1、2.8±1.2和1.3±0.6 pg/样本（分别为对照、应激和恢复阶段）。应激期间血浆OT显著增加（基础值与应激值分别为3.7±1.2与11.7±2.3 pg/ml）。当MD探针位于PVN之外时，OT释放没有增加，表明具有位点特异性。应激对透析液或血浆中的VP水平没有影响。这些结果表明，对应激反应时，OT而非VP释放到PVN和外周血中。这些数据增加了OT在PVN中局部释放参与神经内分泌应激级联反应的可能性。
