Endorphinergic systems and the response to stress

Area of Science:

• Neuroscience
• Endocrinology
• Behavioral Science

Background:

• Endogenous opioid peptides (EOPs) are widely distributed in the central nervous system (CNS), cerebrospinal fluid (CSF), pituitary, plasma, and peripheral organs.
• Intracerebroventricular administration of EOPs induces morphinomimetic effects.

Purpose of the Study:

• To investigate the role of EOPs in the acute and chronic stress response.
• To elucidate the involvement of EOPs in stress-induced physiological and behavioral changes.

Main Methods:

• Biochemical analysis to detect acute stress-evoked release of EOPs from brain, spinal cord, and pituitary.
• Assessment of the sensitivity of endorphinergic systems to chronic stress in adult and developing subjects.

Main Results:

• Biochemical evidence confirms acute stress-induced release of EOPs.
• Endorphinergic systems show sensitivity to chronic stress.
• EOPs mediate stress-induced increases in nociceptive threshold, core temperature, exploration, and grooming behavior.
• EOPs are implicated in anxiety attenuation.
• Endorphinergic control of pituitary secretion and peripheral organ activity during stress is demonstrated.

Conclusions:

• EOPs play a significant role in the overall stress response in both animals and humans.
• These peptides are crucial modulators of physiological and behavioral adaptations to stress.