Abstract
We designed our studies to determine whether blood pressure is elevated in obese Zucker rats compared with lean control rats and to test the importance of the renin-angiotensin and adrenergic nervous systems in long- term blood pressure control in this genetic model of obesity. We monitored mean arterial pressure 24 hours per day using computerized methods in 13- to 14-week-old lean and obese Zucker rats maintained on a fixed, normal sodium intake (3.3 mmol/d). Mean arterial pressure (average of 5 days) was higher in obese (100±1 mm Hg) than in lean (86±1) rats. Although control plasma renin activity was lower in obese than in lean rats (3.66±0.15 versus 5.48±0.11 ng angiotensin l/mL per hour), blood pressure sensitivity to exogenous angiotensin II was greater in obese than in lean rats. Blockade of endogenous angiotensin II receptors with losartan (10 mg/kg per day) for 7 days also caused a greater decrease in blood pressure in obese (36±2 mm Hg, n=6) than in lean (25±1, n=5) rats. However, combined α- and β-adrenergic blockade with terazosin (10 mg/kg per day) and propranolol (10 mg/kg per day), respectively, for 8 days caused only modest decreases in blood pressure in obese (9±3 mm Hg, n=8) and lean (4±2, n=6) rats, despite effective α- and β-adrenergic blockade. These results suggest that increased arterial pressure in obese Zucker rats depends in part on angiotensin II. However, additional mechanisms may also contribute to increased blood pressure in obese Zucker rats.
Original language | English (US) |
---|---|
Pages (from-to) | 1047-1054 |
Number of pages | 8 |
Journal | Hypertension |
Volume | 28 |
Issue number | 6 |
DOIs | |
State | Published - Jan 1 1996 |
Externally published | Yes |
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Keywords
- blood pressure
- kidney
- obesity
- renin
- sodium
- sympathetic nervous system
ASJC Scopus subject areas
- Internal Medicine
Cite this
Hypertension in obese Zucker rats : Role of angiotensin II and adrenergic activity. / Alonso-Galicia, Magdalena; Brands, Michael W; Zappe, Dion H.; Hall, John E.
In: Hypertension, Vol. 28, No. 6, 01.01.1996, p. 1047-1054.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Hypertension in obese Zucker rats
T2 - Role of angiotensin II and adrenergic activity
AU - Alonso-Galicia, Magdalena
AU - Brands, Michael W
AU - Zappe, Dion H.
AU - Hall, John E.
PY - 1996/1/1
Y1 - 1996/1/1
N2 - We designed our studies to determine whether blood pressure is elevated in obese Zucker rats compared with lean control rats and to test the importance of the renin-angiotensin and adrenergic nervous systems in long- term blood pressure control in this genetic model of obesity. We monitored mean arterial pressure 24 hours per day using computerized methods in 13- to 14-week-old lean and obese Zucker rats maintained on a fixed, normal sodium intake (3.3 mmol/d). Mean arterial pressure (average of 5 days) was higher in obese (100±1 mm Hg) than in lean (86±1) rats. Although control plasma renin activity was lower in obese than in lean rats (3.66±0.15 versus 5.48±0.11 ng angiotensin l/mL per hour), blood pressure sensitivity to exogenous angiotensin II was greater in obese than in lean rats. Blockade of endogenous angiotensin II receptors with losartan (10 mg/kg per day) for 7 days also caused a greater decrease in blood pressure in obese (36±2 mm Hg, n=6) than in lean (25±1, n=5) rats. However, combined α- and β-adrenergic blockade with terazosin (10 mg/kg per day) and propranolol (10 mg/kg per day), respectively, for 8 days caused only modest decreases in blood pressure in obese (9±3 mm Hg, n=8) and lean (4±2, n=6) rats, despite effective α- and β-adrenergic blockade. These results suggest that increased arterial pressure in obese Zucker rats depends in part on angiotensin II. However, additional mechanisms may also contribute to increased blood pressure in obese Zucker rats.
AB - We designed our studies to determine whether blood pressure is elevated in obese Zucker rats compared with lean control rats and to test the importance of the renin-angiotensin and adrenergic nervous systems in long- term blood pressure control in this genetic model of obesity. We monitored mean arterial pressure 24 hours per day using computerized methods in 13- to 14-week-old lean and obese Zucker rats maintained on a fixed, normal sodium intake (3.3 mmol/d). Mean arterial pressure (average of 5 days) was higher in obese (100±1 mm Hg) than in lean (86±1) rats. Although control plasma renin activity was lower in obese than in lean rats (3.66±0.15 versus 5.48±0.11 ng angiotensin l/mL per hour), blood pressure sensitivity to exogenous angiotensin II was greater in obese than in lean rats. Blockade of endogenous angiotensin II receptors with losartan (10 mg/kg per day) for 7 days also caused a greater decrease in blood pressure in obese (36±2 mm Hg, n=6) than in lean (25±1, n=5) rats. However, combined α- and β-adrenergic blockade with terazosin (10 mg/kg per day) and propranolol (10 mg/kg per day), respectively, for 8 days caused only modest decreases in blood pressure in obese (9±3 mm Hg, n=8) and lean (4±2, n=6) rats, despite effective α- and β-adrenergic blockade. These results suggest that increased arterial pressure in obese Zucker rats depends in part on angiotensin II. However, additional mechanisms may also contribute to increased blood pressure in obese Zucker rats.
KW - blood pressure
KW - kidney
KW - obesity
KW - renin
KW - sodium
KW - sympathetic nervous system
UR - http://www.scopus.com/inward/record.url?scp=0029808766&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029808766&partnerID=8YFLogxK
U2 - 10.1161/01.HYP.28.6.1047
DO - 10.1161/01.HYP.28.6.1047
M3 - Article
C2 - 8952595
AN - SCOPUS:0029808766
VL - 28
SP - 1047
EP - 1054
JO - Hypertension
JF - Hypertension
SN - 0194-911X
IS - 6
ER -