title: Circulating monoamine oxidase B and phenolsulfotransferase activities in essential hypertensive patients.
abstract: Circulating monoamine oxidase (MAO) and phenolsulfotransferase M and P (PST M, PST P) activities were determined in 24 untreated essential hypertensive patients and in 35 age-matched normotensive healthy controls. These enzymes are involved in the inactivation of monoamines and their metabolites. After lysis of blood, enzymatic activities were determined by radioenzymatic techniques using as substrates [14C]-beta-phenylethylamine for MAO, 3-methoxy-4-hydroxyphenylglycol for PST M and phenol for PST P. MAO activity measured by this method is fully accounted for by platelet MAO B activity. Women presented higher MAO activity than men. Significantly lower MAO-B activities were observed in hypertensive patients, both in men and in women, when compared to normotensive controls. Circulating PST activities, of which more than 80% is platelet-derived, were similar in hypertensive and normotensive subjects. These data suggest that the intracellular serotonin inactivation processes, through MAO and PST, cannot account for the reduction of platelet 5-HT content observed in essential hypertension.
authors.affiliation: U7 INSERM, Department of Pharmacology, Hopital Necker, Paris, France.
authors.forename: P
authors.initials: P
authors.lastname: Guicheney
authors.forename: H
authors.initials: H
authors.lastname: Soliman
authors.forename: J M
authors.initials: JM
authors.lastname: Launay
authors.forename: C
authors.initials: C
authors.lastname: Dreux
authors.forename: P
authors.initials: P
authors.lastname: Meyer
mesh_terms: D000328:Adult; D015239:Arylsulfotransferase; D001792:Blood Platelets / Q000378:metabolism; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000097:blood*; D012701:Serotonin / Q000097:blood; D012737:Sex Factors; D013466:Sulfurtransferases / Q000097:blood*
chemical_list: D012701:Serotonin; D008995:Monoamine Oxidase; D013466:Sulfurtransferases; D015239:Arylsulfotransferase