Related Experiment Videos
Stress increases oxytocin release within the hypothalamic paraventricular nucleus
T Nishioka1, J A Anselmo-Franci, P Li
1Department of Physiology and Pharmacology, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157-1083, USA.
Brain Research
|May 2, 1998
Summary
Stress increases oxytocin (OT) release in the brain and blood. This study shows that the hypothalamic paraventricular nucleus (PVN) releases OT during stress, suggesting a role in the stress response.
Area of Science:
- Neuroscience
- Endocrinology
- Stress Physiology
Background:
- The hypothalamic paraventricular nucleus (PVN) and oxytocin (OT) neurons are implicated in stress responses.
- The specific role of OT release within the PVN during acute stress requires further elucidation.
Purpose of the Study:
- To investigate whether oxytocin (OT) is released into the hypothalamic paraventricular nucleus (PVN) during shaker stress.
- To determine the site specificity and stress-induced changes in OT and vasopressin (VP) release.
Main Methods:
- Microdialysis (MD) was used to measure OT and VP release in the PVN and peripheral blood of male rats.
- Measurements were taken under basal conditions, during, and after 10 minutes of shaker stress (110 cycles/min).
- PVN guide cannulae and venous catheters were surgically implanted for sample collection.
Main Results:
- Shaker stress specifically increased OT levels in both the PVN dialysate and plasma.
- PVN dialysate OT increased from 0.3 pg/sample (control) to 2.8 pg/sample during stress.
- Plasma OT levels significantly rose from 3.7 pg/ml (basal) to 11.7 pg/ml during stress.
- No significant changes in vasopressin (VP) levels were observed in either the PVN or plasma.
- OT release into the PVN was site-specific, as no increase was detected when probes were outside the PVN.
Conclusions:
- Oxytocin (OT), but not vasopressin (VP), is released into the hypothalamic paraventricular nucleus (PVN) and peripheral circulation in response to shaker stress.
- The localized release of OT within the PVN suggests a potential role in the neuroendocrine stress cascade.
- These findings highlight the involvement of central oxytocin pathways in the physiological adaptation to acute stress.