The turnover rates, rate constants and half-life values of neuronal histamine (HA) in 10 nuclei of the rat hypothalamus were estimated from the depletion of HA induced by alpha-fluoromethylhistidine (alpha-FMH: 100 mg/kg, i.p.), a specific inhibitor of histidine decarboxylase, on the presumption that alpha-FMH depletable HA pools represent neuronal ones. Marked variation in the HA turnover rate...

Histamine poisoning is caused by the ingestion of food containing high levels of histamine, a biogenic amine. Histamine could be expected in virtually all foods that contain proteins or free histidine and that are subject to conditions enabling microbial activity. In most histamine-containing foods the majority of the histamine is generated by decarboxylation of the histidine through histidine ...

The role of histamine (HA) as a neurotransmitter in the CNS, although proposed a decade ago (Schwartz, 1975), has been only progressively recognized (reviewed by Schwartz et al., 1980, 1982, 1984; Hough and Green, 1984). One of the key pieces of expenmental evidence has been the demonstration that synthesis of the amine in CNS depends on a specific enzyme, L-histidine decarboxylase (HDC) (Schwa...

E ARLIER OBSERVATIONS of elevated blood and urine histamine levels in myeloproliferative disorders1’2 have recently been confirmed and extended in this laboratory using a sensitive and specific spectrophotofluorometric assay.3 Whole blood and urine histamine content was demonstrated to be increased in uncontrolled polycythemia vera, “spent” polycythemia, and myelofibrosis with myeloid metaplasi...

Histamine and prostaglandins (PGs) play a variety of physiological roles as autacoids, which function in the vicinity of their sources and maintain local homeostasis in the body. They stimulate target cells by acting on their specific receptors, which are coupled to trimeric G proteins. For the precise understanding of the physiological roles of histamine and PGs, it is necessary to clarify the...