title: Does brain histamine contribute to the development of hypertension in spontaneously hypertensive rats?
abstract: Histaminergic neurons of the brain have been implicated in genetic hypertension. We investigated the effect of inhibition of histamine synthesis by alpha-fluoromethylhistidine (alpha-FMH), the irreversible inhibitor of histidine decarboxylase, on the development and maintenance of hypertension in spontaneously hypertensive rats. Young (3-week-old) and adult (7-week-old) rats were treated with alpha-fluoromethylhistidine for 29 and 13 days, respectively. Treatment of spontaneously hypertensive rats and normotensive Wistar-Kyoto rats with alpha-fluoromethylhistidine led to a pronounced decrease in the histidine decarboxylase activity and in the histamine concentration in the brain (hypothalamus, brainstem, cortex-midbrain). In adult spontaneously hypertensive rats, the development of hypertension was not influenced by alpha-fluoromethylhistidine. In young spontaneously hypertensive rats, alpha-fluoromethylhistidine led to a transient delay in the development of hypertension which was followed by a transient tendency to increased blood pressure. It is concluded that histaminergic neurons of the brain play only a subordinate role, if any at all, in the development of hypertension in spontaneously hypertensive rats.
authors.affiliation: Institut für Pharmakodynamik und Toxikologie der Universität, Innsbruck, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Prast
authors.forename: A
authors.initials: A
authors.lastname: Philippu
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D001933:Brain Stem / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D006632:Histamine / Q000096:biosynthesis* / Q000502:physiology; D006640:Histidine Decarboxylase / Q000037:antagonists & inhibitors / Q000378:metabolism; D006973:Hypertension / Q000209:etiology*; D007031:Hypothalamus / Q000378:metabolism; D008636:Mesencephalon / Q000378:metabolism; D008762:Methylhistidines / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
chemical_list: D008762:Methylhistidines; C028309:alpha-fluoromethylhistidine; D006632:Histamine; D006640:Histidine Decarboxylase