title: Altered plasma leucine-enkephalin concentrations in patients with established hypertension may be involved in impaired regulation of blood pressure.
abstract: Leucine-enkephalin is known to modulate cardiovascular activity. In the present study we determined plasma leucine-enkephalin and noradrenaline concentrations in young men with essential hypertension and in normotensives at rest and after bicycle exercise. The essential hypertensive patients had a lower concentration level of resting leucine-enkephalin than the normotensives. Exercise increased leucine-enkephalin in both groups. Noradrenaline was significantly higher in the essential hypertensives than in the normotensives. The central alpha 2-agonist clonidine reduced leucine-enkephalin at rest in the normotensives and prevented its increase during exercise, but had no effect on leucine-enkephalin in the essential hypertensives. These results may reflect an altered interaction between leucine-enkephalin and noradrenaline in essential hypertensives compared to normotensives, possibly contributing to hypertension.
authors.affiliation: Medizinische Poliklinik, Bonn, Federal Republic of Germany.
authors.forename: K
authors.initials: K
authors.lastname: Kraft
authors.forename: F
authors.initials: F
authors.lastname: Kokorsch
authors.forename: J
authors.initials: J
authors.lastname: Diehl
authors.forename: R
authors.initials: R
authors.lastname: Kolloch
authors.forename: K O
authors.initials: KO
authors.lastname: Stumpe
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D003000:Clonidine / Q000627:therapeutic use; D004743:Enkephalin, Leucine / Q000097:blood*; D005080:Exercise Test; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D009638:Norepinephrine / Q000097:blood
chemical_list: D004743:Enkephalin, Leucine; D003000:Clonidine; D009638:Norepinephrine