Open AccessSirkadiese sekresiepatrone van ß-endorfien en leusienenkefalien
Author(s) -
E. H. de Wet,
J. M. C. Oosthuizen
Publication year - 1992
Publication title -
suid-afrikaanse tydskrif vir natuurwetenskap en tegnologie/die suid-afrikaanse tydskrif vir natuurwetenskap en tegnologie
Language(s) - English
Resource type - Journals
eISSN - 2222-4173
pISSN - 0254-3486
DOI - 10.4102/satnt.v11i1.516
Subject(s) - circadian rhythm , endocrinology , melatonin , enkephalin , medicine , radioimmunoassay , met enkephalin , neuropeptide , leucine , secretion , hypothalamus , endorphins , chemistry , biology , opioid , biochemistry , amino acid , receptor
ß-endorphin and leucine enkephalin are neuropeptides with potent opioid activity. In a study to investigate the circadian secretion patterns of the above-mentioned, blood samples were collected hourly from 12 healthy males who were subjected to the experiment for 24 hours. Radioimmunoassays were used in the analysis of plasma samples for ß-endorphin and leucine enkephalin. Peak concentrations of ß-endorphin were demonstrated from 08:00-09:00, while peak concentrations of leucine enkephalin occured from 23:00-07:00. Trough concentrations of ß-endorphin occurred from 24:00-05:00, while trough concentrations of leucine enkephalin were demonstrated from 09:00-12:00. The illustrated circadian secretion pattern for ß-endorphin simulates the well-known circadian rhythm of cortisol. The answer to this may be in the fact that ß-endorphin and corticotropin stem from the same precursor. The illustrated circadian secretion pattern for leucine enkephalin simulates that of melatonin. The reason for this is unclear