Related Experiment Video
Updated: Jul 30, 2026

A Method of Nodose Ganglia Injection in Sprague-Dawley Rat
Published on: November 25, 2014
Stress-induced release of prolactin: blockade by dexamethasone and naloxone may indicate beta-endorphin mediation
Abstract:
Basal levels of immunoreactive (ir) beta-endorphin, corticotropin (ACTH), and prolactin (PRL) in plasma of male rats decrease after dexamethasone pretreatment (400 microgram/kg at 24 hr and 200 microgram/kg at 2 hr before). Inescapable electric footshocks increase ir-beta-endorphin, ACTH, and PRL plasma levels and this effect is blocked by dexamethasone pretreatment. Morphine (20 mg/kg) also increases ir-beta-endorphin, ACTH, and PRL levels. Dexamethasone pretreatment blocks the morphine-induced release of ir-beta-endorphin but does not prevent the morphine-induced release of PRL. Naloxone, the opiate antagonist, decreases basal plasma levels of PRL and partially blocks the stress-induced increase of PRL, but it has no effect on the basal or stress-induced release of ir-beta-endorphin. These results are consistent with the proposal that beta-endorphin may interact with an opiate receptor involved in the regulation of PRL secretion.
More Related Videos
09:12Assessing Cellular Stress and Inflammation in Discrete Oxytocin-secreting Brain Nuclei in the Neonatal Rat Before and After First Colostrum Feeding
Published on: November 14, 2018
05:40Dural Stimulation and Periorbital von Frey Testing in Mice As a Preclinical Model of Headache
Published on: July 29, 2021
Related Concept Videos
Feedback Loops
Hypothalamic-Pituitary Axis
Desensitization and Tachyphylaxis
Several...
Regulation of Hormone Secretion
Humoral stimuli,...
Drugs Affecting Neurotransmitter Synthesis
Cushing Syndrome II: Pathophysiology