Effects of Stress on Brain Neuronal Network and Modification of Benzodiazepines and Nitrous Oxide

Dual-probe microdialysis was used to investigate the release of noradrenaline in the medial前frontal cortex (mPFC) during stress. Male albino rats of a Wistar-derived strain were used forthe experiments. For pose a micro-dialysis probe was implanted in the vicinity of the locuscoeruleus (LC) and a second probe was placed in the ipsilateral PFC. Receptor specific antagonistsacting in the α - D22 - D2 adrenoceptor (idazoxane). GABA - D2A - D2 (bicuculline)，GABA - D2B - D2 (CGP52432), acetylacholine (atropine)，corticotropine releasing factor (CRF) (CP 154,526), NMDA glutamate (CPP)，non-NMDA glutamate Receptor (DNQX) were infused into the LC by retrograde dialysiswhereas extracellular NA was recorded in the ipsilateral PFC. During infusion of the variouscompounds rat gently handled for 10min . infusion of idazoxane potentiates the handling-inducedincrease in the release of NA in the PFC. Infusion of atropine，bicuculline CGP52432和DNQX were without effect in the handling response. Infusion of thenon-peptide CRF antagonist CP 154、526和CPP suppressed the simulation of NA during handlingstress, and benzodiazepine anxiolytic (midazolam) also suppressed.It is concluded that α - D22 - D2，NMDA glutamate and CRF receptors modify the handling stress response of LC neurons，benzodiazepine anxiolytics also modify it.这些数据suggest no major role for GABAergic，nor cholinergic affernts to the LC in mediating the压力反应。

Dual-probe microdialysis was used to investigate the release of noradrenaline in the medial prefrontal cortex (mPFC) during stress. Male albino rats of a Wistar-derived strain were used for the experiments. For that purpose a micro-dialysis probe was implanted in the vicinity of the locus coeruleus (LC) and a second probe was placed in the ipsilateral PFC. Receptor specific antagonists acting in the αィイD22ィエD2 adrenoceptor (idazoxane). GABAィイD2AィエD2 (bicuculline), GABAィイD2BィエD2 (CGP52432), acetylacholine (atropine), corticotropine releasing factor (CRF) (CP 154,526), NMDA glutamate (CPP), non-NMDA glutamate Receptor (DNQX) were infused into the LC by retrograde dialysis, whereas extracellular NA was recorded in the ipsilateral PFC. During infusion of the various compounds rat were gently handled for 10 min.Infusion of idazoxane potentiates the handling-induced increase in the release of NA in the PFC. Infusion of atropine, bicuculline CGP52432 and DNQX were without effect in the handling response. Infusion of the non-peptide CRF antagonist CP 154,526 and CPP suppressed the simulation of NA during handling stress, and benzodiazepine anxiolytic (midazolam) also suppressed.It is concluded that αィイD22ィエD2, NMDA glutamate and CRF receptors modify the handling stress response of LC neurons, and benzodiazepine anxiolytics also modify it. These data suggest no major role for GABAergic, nor cholinergic affernts to the LC in mediating the stress response.