Diurnal fluctuation in levels of histamine metabolites in cerebrospinal fluid of rhesus monkey.
In samples of ventricular cerebrospinal fluid (CSF) that were collected from a conscious, restrained rhesus monkey at intervals of 30 90 min, levels of the histamine metabolites, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), were determined by gas chromatography-mass spectrometry. Levels of t-MH and t-MIAA each showed time-related fluctuations. Peak and trough concentrations of t-MIAA, the product of t-MH, paralleled, but lagged about 2 h behind, the levels of t-MH. Within the first 3 h of illumination, metabolite levels increased more than 3-fold; they fell sharply within the first 3 h of darkness. Mean levels of t-MH and t-MIAA were significantly higher during periods of illumination than of darkness. Fluctuations in the levels of pros-methylimidazoleacetic acid (p-MIAA), an endogenous isomer of t-MIAA that is not a histamine metabolite, were markedly different from those of t-MH or t-MIAA; p-MIAA levels peaked only at the middle of the dark period. The time-related fluctuations in levels of t-MH and t-MIAA, but not p-MIAA, are similar to the daily rhythmic changes observed in monkey CSF for the levels of other central neurotransmitters and peptide neurohormones.
Prell
G D
GD
Department of Pharmacology, Mount Sinai School of Medicine, University of New York, New York 10029.
Khandelwal
J K
JK
Burns
R S
RS
Green
J P
JP
D000818:Animals; D002940:Circadian Rhythm; D006632:Histamine / Q000134:cerebrospinal fluid*; D007093:Imidazoles / Q000134:cerebrospinal fluid; D008253:Macaca mulatta; D008297:Male; D008761:Methylhistamines / Q000134:cerebrospinal fluid
D007093:Imidazoles; D008761:Methylhistamines; C002667:methylimidazoleacetic acid; D006632:Histamine; C020404:tele-methylhistamine