Presence of immunoreactive beta-endorphin in normal human plasma: a concomitant release of beta-endorphin with adrenocorticotropin after metyrapone administration.
To elucidate whether or not beta-endorphin exists in plasma of normal subjects, plasma extracts obtained before and after metyrapone administration were subjected to gel exclusion chromatography, and fractions obtained were assayed by a sensitive radioimmunoassay for beta-endorphin. The basal plasma level of beta-endorphin was 5.8 +/- 1.1 pg/ml (mean +/- SE, n = 5), which rose significantly to the level of 48.9 +/- 3.8 pg/ml after a single oral dose (30 mg/kg of body wt) of metyrapone administration (P less than 0.001). Plasma ACTH levels also increased from the mean basal level of 73 +/- 4 pg/ml to 269 +/- 41 pg/ml after metyrapone administration. These results indicate that beta-endorphin, distinct from beta-lipotropin, exists in normal human plasma and that it is released from the pituitary concomitantly with ACTH.
ACESSO AO ARTIGOhttp://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=371906
- Distribution of beta-endorphin immunoreactivity in normal human pituitary.
- Immunoreactive beta-endorphin in a subpopulation of mouse spleen macrophages.
- beta-endorphin-(1-27) is an antagonist of beta-endorphin analgesia.
- Increased central immunoreactive beta-endorphin content in patients with Wernicke-Korsakoff syndrome and in alcoholics.
- beta-endorphin is a potent analgesic agent.