Chronic Intermittent Ethanol and Acute Stress Similarly Modulate BNST CRF Neuron Activity via Noradrenergic Signaling. (18th June 2019)

• Record Type: Journal Article
• Authors: Snyder, Angela E.; Salimando, Gregory J.; Winder, Danny G.; Silberman, Yuval
• Is Part Of: Alcoholism. Volume 43:Number 8(2019)
• Page Start: 1695
• Page End: 1701
• Publication Date: 2019-06-18
• Subjects: Bed Nucleus of the Stria Terminalis -- Adrenergic Receptors -- Corticotropin‐Releasing Factor -- Norepinephrine -- Ethanol; Alcoholism -- Periodicals; Alcoholism -- Periodicals; Alcoolisme; Electronic journals; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.861005
• DOI: 10.1111/acer.14118
• Languages: English
• ISSNs: 0145-6008

Abstract

Abstract : Background: Relapse is a critical barrier to effective long‐term treatment of alcoholism, and stress is often cited as a key trigger to relapse. Numerous studies suggest that stress‐induced reinstatement to drug‐seeking behaviors is mediated by norepinephrine (NE) and corticotropin‐releasing factor (CRF) signaling interactions in the bed nucleus of the stria terminalis (BNST), a brain region critical to many behavioral and physiologic responses to stressors. Here, we sought to directly examine the effects of NE on BNST CRF neuron activity and determine whether these effects may be modulated by chronic intermittent EtOH (CIE) exposure or a single restraint stress. Methods: Adult male CRF‐ tomato reporter mice were treatment‐naïve, or either exposed to CIE for 2 weeks or to a single 1‐hour restraint stress. Effects of application of exogenous NE on BNST CRF neuron activity were assessed via whole‐cell patch‐clamp electrophysiological techniques. Results: We found that NE depolarized BNST CRF neurons in naïve mice in a β‐adrenergic receptor (AR)–dependent mechanism. CRF neurons from CIE‐ or stress‐exposed mice had significantly elevated basal resting membrane potential compared to naïve mice. Furthermore, CIE and stress individually disrupted the ability of NE to depolarize CRF neurons, suggesting that both stress and CIE utilize β‐AR signaling to modulate BNST CRF neurons. Neither stress nor CIE altered the ability of exogenous NE to inhibit evoked glutamatergic transmission onto BNST CRF neurons as shown in naïve mice, a mechanism previously shown to be α‐AR–dependent. Conclusions: Altogether, these findings suggest that stress and CIE interact with β‐AR signaling to modulate BNST CRF neuron activity, potentially disrupting the α/β‐AR balance of BNST CRF neuronal excitability. Restoration of α/β‐AR balance may lead to novel therapies for the alleviation of many stress‐related disorders. Abstract : Corticotropin‐releasing factor (CRF) neurons in the bed nucleus of the stria terminalis (BNST) are critical for stress‐related ethanol behaviors. In naïve mice, norepinephrine modulates BNST CRF neurons via excitatory β ‐adrenoceptor and inhibitory β ‐adrenoceptor mechanisms. Stress and chronic ethanol target endogenous β ‐adrenoceptor mechanisms in BNST CRF neurons without altering β ‐adrenoceptor signaling. These findings suggest stress and chronic ethanol promote BNST CRF neuron activation by altering α / β ‐adrenoceptor balance. Restoring α / β ‐adrenoceptor balance may be a novel therapeutic approach for stress‐related ethanol behaviors.