Disease relevance of C05828

• The urinary excretion of histamine and its main metabolite, 1-methyl-4-imidazoleacetic acid (MeImAA), was determined in 30 adult patients with the clinical diagnosis of urticaria pigmentosa (UP) [1].
• The concentration of methylimidazole-acetic acid in lumbar CSF from schizophrenic patients, patients with subarachnoidal haemorrhage, or patients with rheumatic disease was in the range of that in healthy volunteers [2].
• This indicated a higher sensitivity for diagnosing mild mastocytosis on the basis of levels of serum tryptase as opposed to urinary methylimidazoleacetic acid [3].
• Increased urinary methylimidazoleacetic acid (MelmAA) as an indicator of systemic mastocytosis [4].
• A significant increase in heat-stable NCA, however, was found in patients with pruritus and abnormal high values of MelmAA [5].

High impact information on C05828

• After an initial lag phase lasting 3-6 min, the cell-associated radioactivity accumulates as methylimidazoleacetic acid at a linear rate substantially enhanced over that without diamine oxidase [6].
• In brains of saline-treated rats, most radioactivity recovered was due to tele-methylhistamine and tele-methylimidazoleacetic acid [7].
• It is generally accepted that in mammalian brain histamine is metabolized solely by histamine methyltransferase (HMT), to form tele-methylhistamine, then oxidized to tele-methylimidazoleacetic acid [7].
• The concentration of methylimidazole-acetic acid in lumbar CSF from healthy volunteers was below 1 ng/ml [2].
• A positive correlation between the number of mast cells in sections of the bone marrow and the urinary excretion of the main histamine metabolite tele-methylimidazoleacetic acid was found [8].

Biological context of C05828

• The urinary excretion of histamine and its metabolites methylhistamine (MeHi) and methylimidazoleacetic acid (MeImAA) was measured during the menstrual cycle in nine healthy women, one allergic woman and three non-pregnant women with anovulatory regular cycles [9].
• The urinary excretion of histamine and its metabolites, methylhistamine, methylimidazoleacetic acid and imidazoleacetic acid, was measured under standardized dietary conditions in 24 women with normal pregnancies and in eleven patients with toxaemia of pregnancy [10].

Anatomical context of C05828

• The bone marrow in urticaria pigmentosa and systemic mastocytosis. Cell composition and mast cell density in relation to urinary excretion of tele-methylimidazoleacetic acid [8].
• The metabolites of histamine, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), were measured in cerebrospinal fluid (CSF) from 47 subjects with neurological disorders and healthy controls [11].
• The effect of histamine and its specific metabolites, tele-methylhistamine and tele-methylimidazoleacetic acid (MeImAA), on the Con A lymphocyte mitogen response was also studied in healthy controls [12].

Analytical, diagnostic and therapeutic context of C05828

• MIAA was measured by high performance liquid chromatography (HPLC) [13].
• Altered retention of derivatives of tele-methylimidazoleacetic acid in acid-hydrolyzed samples of brain measured by capillary gas chromatography and mass spectrometry [14].

References