Diurnal variations of S-adenosyl-L-methionine and adenosine content in the rat pineal gland.
S-adenosylmethionine and adenosine levels in the rat pineal gland were determined by high-performance liquid chromatography after fractionation of the pineal extracts. The concentration of S-adenosylmethionine follows a circadian rhythm and is about three times higher during the day (2.5 nmol/gland) than the night (1.1 nmol/gland). The variations in the level of adenosine are apparently more complex. Over the 24 hours period there are two maxima at 03.00 (120 pmol/gland) and 15.00 hrs (100 pmol/gland) and one minimum at 09.00 hrs (50 pmol/gland). In addition, only an ultradian rhythm with a period of 12 hrs and an acrophase of 3 hrs can be evinced by computer analysis.
D000241:Adenosine / Q000378:metabolism*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002940:Circadian Rhythm; D008297:Male; D010870:Pineal Gland / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012436:S-Adenosylmethionine / Q000378:metabolism*
D012436:S-Adenosylmethionine; D000241:Adenosine