beta-Endorphin modulation of pressor response to hyperventilation in hypertensive patients.
After hyperventilation, systolic and diastolic blood pressure (BP) significantly decreased in 14 hypertensive patients (group 1), did not change in 9 (group 2) and increased in 8 (group 3). Basal BP, norepinephrine and dynorphin B levels were higher in group 1 than in groups 2 and 3. The decrease in BP after hyperventilation was associated with a decrease in plasma norepinephrine, Met-enkephalin and dynorphin B and an increase in beta-endorphin. Naloxone abolished the hyperventilation-induced BP and norepinephrine decreases. Our findings indicate that hyperventilation may select hypertensive patients with different sympatho-adrenergic activity and that the increase in beta-endorphin reduces BP response to hyperventilation in patients with high sympatho-adrenergic tone.
Fontana
Fiorella
F
Dipartimento di Medicina Interna, Cardioangiologia, Epatologia, Ospedale S. Orsola, Via Massarenti 9, Bologna, Italy. ffontana@almadns.unibo.it
Bernardi
Pasquale
P
Spampinato
Santi
S
Toro
Rosanna Di
RD
Bugiardini
Raffaele
R
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D018592:Cross-Over Studies; D004399:Dynorphins / Q000097:blood; D004744:Enkephalin, Methionine / Q000097:blood; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology*; D006985:Hyperventilation / Q000097:blood* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009270:Naloxone / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood; D013997:Time Factors; D001615:beta-Endorphin / Q000097:blood*
D009270:Naloxone; D004744:Enkephalin, Methionine; D001615:beta-Endorphin; D004399:Dynorphins; D009638:Norepinephrine