Role of sympathetic activity in blood pressure reduction with low calorie regimen.
To investigate the effects of a low calorie regimen on sympathetic function and its relation to blood pressure response, 22 untreated obese essential hypertensive patients (50 +/- 2 years, body mass index 29 +/- 1 kg/m2) were hospitalized and a diet was prescribed of 2,000 kcal/day for 5 days (control period) followed by 800 kcal/day for 21 days without changing salt intake (8-10 g/day). The dose of intravenous phenylephrine infusion needed to elevate systolic blood pressure 20 mm Hg (CD20) and the 24-hour urinary excretion of norepinephrine (UNE) were measured. During the low calorie period, blood pressure normalized in 14 patients (responder group, 124 +/- 3/79 +/- 4 mm Hg) and eight remained hypertensive (poor responder group, 158 +/- 6/103 +/- 3 mm Hg). At the control period, blood pressure and body mass index were similar, but the responder group had higher UNE (134 +/- 15 micrograms/day) and CD20 (127 +/- 11 micrograms) than the poor responder group (89 +/- 6 micrograms/day and 79 +/- 13 micrograms, respectively). During the low calorie period, both UNE (87 +/- 15 micrograms/day) and CD20 (74 +/- 10 micrograms) decreased in the responder group; no change was seen in the poor responder group. Changes in UNE and systolic blood pressure were correlated (r = 0.6, p less than 0.05). In conclusion, suppression of sympathetic activity plays a role in blood pressure reduction during moderate caloric restriction.
Kushiro
T
T
Department of Cardiology, Surugadai Nihon University Hospital, Tokyo, Japan.
Kobayashi
F
F
Osada
H
H
Tomiyama
H
H
Satoh
K
K
Otsuka
Y
Y
Kurumatani
H
H
Kajiwara
N
N
D001794:Blood Pressure / Q000502:physiology*; D015992:Body Mass Index; D002149:Energy Intake; D005260:Female; D006801:Humans; D006973:Hypertension / Q000178:diet therapy / Q000503:physiopathology / Q000652:urine; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000652:urine; D009765:Obesity / Q000178:diet therapy / Q000503:physiopathology / Q000652:urine; D013564:Sympathetic Nervous System / Q000503:physiopathology*
D009638:Norepinephrine