RT Journal Article
SR Electronic
T1 Estrous Cycle Mediates Midbrain Neuron Excitability Altering Social Behavior upon Stress
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 736
OP 748
DO 10.1523/JNEUROSCI.1504-22.2022
VO 43
IS 5
A1 Mary R. Shanley
A1 Yuka Miura
A1 Christopher A. Guevara
A1 Amanda Onoichenco
A1 Rufina Kore
A1 Emine Ustundag
A1 Rania Darwish
A1 Lauren Renzoni
A1 Ashley Urbaez
A1 Ella Blicker
A1 Alec Seidenberg
A1 Teresa A. Milner
A1 Allyson K. Friedman
YR 2023
UL http://www.jneurosci.org/content/43/5/736.abstract
AB The estrous cycle is a potent modulator of neuron physiology. In rodents, in vivo ventral tegmental area (VTA) dopamine (DA) activity has been shown to fluctuate across the estrous cycle. Although the behavioral effect of fluctuating sex steroids on the reward circuit is well studied in response to drugs of abuse, few studies have focused on the molecular adaptations in the context of stress and motivated social behaviors. We hypothesized that estradiol fluctuations across the estrous cycle acts on the dopaminergic activity of the VTA to alter excitability and stress response. We used whole-cell slice electrophysiology of VTA DA neurons in naturally cycling, adult female C57BL/6J mice to characterize the effects of the estrous cycle and the role of 17β-estradiol on neuronal activity. We show that the estrous phase alters the effect of 17β-estradiol on excitability in the VTA. Behaviorally, the estrous phase during a series of acute variable social stressors modulates subsequent reward-related behaviors. Pharmacological inhibition of estrogen receptors in the VTA before stress during diestrus mimics the stress susceptibility found during estrus, whereas increased potassium channel activity in the VTA before stress reverses stress susceptibility found during estrus as assessed by social interaction behavior. This study identifies one possible potassium channel mechanism underlying the increased DA activity during estrus and reveals estrogen-dependent changes in neuronal function. Our findings demonstrate that the estrous cycle and estrogen signaling changes the physiology of DA neurons resulting in behavioral differences when the reward circuit is challenged with stress.SIGNIFICANCE STATEMENT The activity of the ventral tegmental area encodes signals of stress and reward. Dopaminergic activity has been found to be regulated by both local synaptic inputs as well as inputs from other brain regions. Here, we provide evidence that cycling sex steroids also play a role in modulating stress sensitivity of dopaminergic reward behavior. Specifically, we reveal a correlation of ionic activity with estrous phase, which influences the behavioral response to stress. These findings shed new light on how estrous cycle may influence dopaminergic activity primarily during times of stress perturbation.