Hypertension, Vol 7, 913-922, Copyright © 1985 by American Heart Association
J Yamamoto, S Akabane, H Yoshimi, M Nakai and M Ikeda
Cardiovascular hemodynamics (microspheres) and plasma norepinephrine and
epinephrine levels at rest and during short-term shaker stress were
investigated in conscious spontaneously hypertensive rats and Wistar- Kyoto
rats, with or without oral taurine (1.5%) treatment for 8 weeks. Taurine
effects were evaluated by comparing data on the taurine-treated and
untreated rats. Taurine affected neither the resting hemodynamics nor the
resting plasma catecholamine levels in spontaneously hypertensive and
Wistar-Kyoto rats. Taurine slightly but significantly reduced the left
ventricular/body weight ratio in the spontaneously hypertensive rats (p
less than 0.05) and caused an insignificant 10 mm Hg decrease in the
resting mean arterial pressure. Spontaneously hypertensive and Wistar-Kyoto
rats responded in a qualitatively similar manner to stress, as evidenced by
resistance-dominated increases in mean arterial pressure and increases in
heart rate, with a blood flow redistribution from splanchnic, cutaneous,
and testicular to skeletal muscle and cerebral circulations and by
increases in plasma norepinephrine and epinephrine levels. These changes
were more marked in the spontaneously hypertensive rats. Taurine
significantly reduced the stress values of mean arterial pressure
(untreated, 189 +/- 4 (SE) mm Hg; treated, 166 +/- 4 mm Hg in the
spontaneously hypertensive rats; p less than 0.05), while it significantly
reduced stress values of heart rate in spontaneously hypertensive and
Wistar-Kyoto rats (p less than 0.05). Taurine also blunted the stress
values of splanchnic, testicular, and cutaneous vascular resistance in the
spontaneously hypertensive rats. There were no or only slight regional
effects in the Wistar-Kyoto rats. Taurine substantially decreased plasma
levels of norepinephrine (untreated, 615 +/- 76 pg/ml; treated, 383 +/- 49
pg/ml) and epinephrine (untreated, 892 +/- 187 pg/ml; treated, 232 +/- 59
pg/ml) during stress in the spontaneously hypertensive rats. These results
indicate that chronic taurine treatment attenuates short-term shaker
stress-induced hemodynamic and plasma catecholamine changes in
spontaneously hypertensive rats.
ARTICLES
Effects of taurine on stress-evoked hemodynamic and plasma catecholamine changes in spontaneously hypertensive rats
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