Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1988-12-12
pubmed:abstractText
Based on prior observations that both beta-endorphin and exercise stimulate natural killer (NK) cell activity, we have examined the hypothesis that the release of endogenous opioids during the stress of acute exercise may mediate this NK cell augmentation. Eight healthy young women underwent a maximal bicycle ergometer exercise test with prior in vivo administration of a placebo and an opioid antagonist, naloxone (100 micrograms/kg), in a randomized, blind protocol. Exercise after the placebo injection was accompanied by a dramatic rise in NK activity, as well as an increase in the percentage of lymphocytes bearing the NK cell surface markers Leu 11a and Leu 19. Significant stimulation of NK activity was observed with beta-endorphin in vitro before exercise, but after exercise, beta-endorphin had a nonsignificant inhibitory effect. When these experiments were carried out in the presence of naloxone in vivo, the rise in NK activity after exercise was no longer significant. Naloxone did not significantly alter the rise in Leu 11a+ or Leu 19+ cell after exercise, as compared with the placebo. Finally, when naloxone was given to the subjects beforehand, exercise no longer completely blocked the in vitro beta-endorphin stimulation of NK cells. In conclusion, our observations that the exercise-induced augmentation of NK activity and the lack of effect of beta-endorphin in vitro on NK activity after exercise are both significantly attenuated by prior administration of naloxone suggest that the opioid system may play a major role in the modulation of NK cells during physiologic stress.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2143
pubmed:author
pubmed:issnType
Print
pubmed:volume
112
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
544-52
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Endogenous opioids and the exercise-induced augmentation of natural killer cell activity.
pubmed:affiliation
Geriatric Research, Education, and Clinical Center, Veterans Administration Medical Center, Sepulveda, CA 91343.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Randomized Controlled Trial, Research Support, Non-U.S. Gov't