RT Journal Article
SR Electronic
T1 The vagus nerve is critical for regulation of hypothalamic-pituitary-adrenal axis responses to acute stress
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.06.03.446790
DO 10.1101/2021.06.03.446790
A1 Bailey N. Keller
A1 Angela E. Snyder
A1 Caitlin R. Coker
A1 Elizabeth A. Aguilar
A1 Mary K. O’Brien
A1 Sarah S. Bingaman
A1 Amy C. Arnold
A1 Andras Hajnal
A1 Yuval Silberman
YR 2021
UL http://biorxiv.org/content/early/2021/06/03/2021.06.03.446790.abstract
AB The hypothalamic pituitary adrenal (HPA) axis is a critical regulator of physiologic and psychological responses to acute and chronic stressors. HPA axis function is control by numerous feedback inhibitory mechanisms, disruptions of which can lead to various psychiatric conditions, such as depression, posttraumatic stress disorder, and schizophrenia. Vagus nerve stimulation has been shown to be efficacious in the treatment of in these various mental health issues potentially via modulation of HPA axis function, but the mechanisms by which the vagus nerve may regulate HPA function has not been fully elucidated. In the present studies, we sought to test the hypothesis that the vagus nerve is a critical regulator of HPA function. Neuroendocrine function and neurocircuit changes in corticotropin releasing factor (CRF) neurons in the paraventricular nucleus of the hypothalamus (PVN) were examined following acute stress after subdiaphragmatic left vagotomy (VX) in adult male Sprague-Dawley rats. We found that VX mimics HPA activation seen in sham surgery animals exposed to acute restraint stress, particularly increased plasma corticosterone levels, elevated PVN CRF mRNA, and increased action potential firing of putative CRF neurons in PVN brain slices. Furthermore, VX animals exposed to acute restraint stress showed increased elevations of plasma corticosterone and PVN CRF mRNA which may be due to lack of compensatory PVN GABAergic signaling in response to acute stress. Both Sham/Stress and VX/no stress conditions increased action potential firing in putative PVN CRF neurons, but this effect was not seen in the VX/stress condition, suggesting that not all forms of stress compensation are lost following VX. Overall, these findings suggest that the vagus nerve may play a critical role in regulating HPA axis function via modulation of local PVN neurocircuit activity.Competing Interest StatementThe authors have declared no competing interest.