Hypertension, Vol 8, 103-108, Copyright © 1986 by American Heart Association
CL Seidel and R Strong
The purpose of this study was to determine if any changes occurred in the
basal and stimulated rates of oxygen consumption and lactate production of
thoracic aortas from spontaneously hypertensive rats (SHR) and renal and
deoxycorticosterone acetate (DOCA)-salt hypertensive rats, and, if so,
whether these changes were similar in these three models of hypertension.
Rings of thoracic aorta were placed in an isothermic (37 degrees C) muscle
bath, and isometric tension development, oxygen consumption, and lactate
production were measured. The results indicated that under basal conditions
oxygen consumption, but not lactate production, was higher in aortas from
all three hypertensive models; the elevation above control was greatest in
the renal model (95%) and smallest in SHR (34%). On stimulation with 60 mM
KCl, a significant increase in oxygen consumption above basal value
occurred in all aorta samples (p less than 0.05); however, lactate
production was increased above basal only in aortas from hypertensive
animals. Only in aortas from renal and DOCA-salt models was the rate of
oxygen consumption during stimulation significantly greater than that of
their normotensive controls (p less than 0.05). Developed active stress in
response to KCl was the same in all groups, and when the change in lactate
production or oxygen consumption was expressed relative to the amount of
active stress developed, no differences were observed. These results
suggest that, 1) compared to values in aortas from normotensive animals,
only the basal rate of oxygen consumption is higher; 2) this higher level
of basal metabolic activity is not associated with an alteration in the
metabolic cost of force development.(ABSTRACT TRUNCATED AT 250 WORDS)
ARTICLES
Metabolic characteristics of aorta from spontaneously hypertensive and renal and deoxycorticosterone acetate-salt hypertensive rats