Rostral-caudal concentration gradients of histamine metabolites in human cerebrospinal fluid.
The metabolites of histamine, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), have a large concentration gradient between cisternal and lumbar CSF in the rhesus monkey. The possibility of a t-MH and/or t-MIAA gradient in man was studied in sequential samples of CSF withdrawn from the lumbar space from a healthy male. The mean levels of t-MH and t-MIAA in the 14-16 ml segment of CSF from 6 male volunteers was also measured. pros-Methylimidazoleacetic acid (p-MIAA), an endogenous isomer of t-MIAA that is not derived from histamine, was also measured. Levels of t-MH, t-MIAA and p-MIAA were measured by gas chromatography-mass spectrometry. With increasing volumes of CSF removed, t-MH and t-MIAA levels increased linearly (p less than 0.01) when plotted against the midpoints of each volume segment. Levels of t-MH and t-MIAA from the volunteers showed little variation; the means of the levels were within 15% of the respective regression lines of the points from the single subject. In contrast, p-MIAA levels showed no gradient (p greater than 0.6) in serially removed CSF; the individual levels in CSF from the volunteers on unrestricted diets varied widely, suggestive of a dietary influence on p-MIAA levels in the CNS. The concentration gradient of histamine metabolites in CSF confirms the rostral-caudal gradient observed in monkey and argues against plasma or spinal cord as major sources of these metabolites.(ABSTRACT TRUNCATED AT 250 WORDS)
Prell
G D
GD
Department of Pharmacology, Mount Sinai School of Medicine, University of New York, NY 10029.
Khandelwal
J K
JK
LeWitt
P A
PA
Green
J P
JP
D000328:Adult; D008401:Gas Chromatography-Mass Spectrometry; D006632:Histamine / Q000134:cerebrospinal fluid*; D006801:Humans; D007093:Imidazoles / Q000134:cerebrospinal fluid*; D008297:Male; D008761:Methylhistamines / Q000134:cerebrospinal fluid*; D009928:Organ Specificity; D012016:Reference Values
D007093:Imidazoles; D008761:Methylhistamines; C002667:methylimidazoleacetic acid; D006632:Histamine; C020404:tele-methylhistamine