Lack of circadian rhythm in plasma levels of 3,4-dihydroxyphenylethyleneglycol in healthy human subjects

✍ Scribed by Trevor Dennis; Chawki Benkelfat; Yvan Touitou; André Auzeby; Marie-France Poirier; Bernard Scatton; Henri Lôo

• Publisher: Springer
• Year: 1986
• Tongue: English
• Weight: 447 KB
• Volume: 90
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00174063

✦ Synopsis

In order to investigate the possible existence of a circadian rhythm in plasma free and sulfate-conjugated 3,4-dihydroxyphenylethyleneglycol (DOPEG), the plasma levels of this metabolite (and for comparison, of melatonin and cortisol) were measured in seven healthy volunteers at 4-h intervals over a period of 24 h. Plasma concentrations of melatonin and cortisol showed distinct diurnal variations with acrophases at 2.5 h and 8.5 h, respectively. In contrast, plasma free DOPEG levels were relatively stable over the 24-h period studied. Sulfate-conjugated and free + sulfate-conjugated DOPEG levels showed a slight, non-significant increase in the early afternoon. These results indicate that in contrast to plasma 3-methoxy 4-hydroxyphenylethyleneglycol, plasma free and conjugated DOPEG levels do not exhibit a circadian rhythm.