TY - JOUR
T1 - Mineralocorticoids upregulate arterial contraction to epidermal growth factor
AU - Florian, Jennifer A.
AU - Dorrance, Anne
AU - Webb, R. Clinton
AU - Watts, Stephanie W.
PY - 2001
Y1 - 2001
N2 - The present studies test the hypothesis that contraction to EGF is dependent on mineralocorticoids and/or an elevation in systolic blood pressure (SBP). Endothelium-denuded thoracic aortas from sham normotensive, Nω-nitro-L-arginine (L-NNA) hypertensive, Wistar-Kyoto (WKY), and spontaneously hypertensive rats (SHR) were used in isolated tissue-bath experiments. Maximal contraction to epidermal growth factor [EGF; percentage of phenylephrine (PE; 10 umol/l)-induced contraction] was greater in strips from L-NNA (32 ± 5%) and SHR (53 ± 8%) rats compared with sham and WKY rats (17 ± 1 and 12 ± 4%, respectively). Wistar-Furth rats became only mildly hypertensive when given DOCA salt (134 ± 6 mmHg) compared with Wistar rats (176 ± 9 mmHg), but aortas from both strains had a similarly enhanced contraction to EGF (∼9 times the maximal contraction of sham aorta). Furthermore, in vitro incubation of aortas from Wistar and Wistar-Furth rats with aldosterone (10 nmol/l) increased EGF-receptor mRNA expression by >50%. These data indicate that arterial contraction to EGF may occur independent of hypertension and be stimulated by mineralocorticoids.
AB - The present studies test the hypothesis that contraction to EGF is dependent on mineralocorticoids and/or an elevation in systolic blood pressure (SBP). Endothelium-denuded thoracic aortas from sham normotensive, Nω-nitro-L-arginine (L-NNA) hypertensive, Wistar-Kyoto (WKY), and spontaneously hypertensive rats (SHR) were used in isolated tissue-bath experiments. Maximal contraction to epidermal growth factor [EGF; percentage of phenylephrine (PE; 10 umol/l)-induced contraction] was greater in strips from L-NNA (32 ± 5%) and SHR (53 ± 8%) rats compared with sham and WKY rats (17 ± 1 and 12 ± 4%, respectively). Wistar-Furth rats became only mildly hypertensive when given DOCA salt (134 ± 6 mmHg) compared with Wistar rats (176 ± 9 mmHg), but aortas from both strains had a similarly enhanced contraction to EGF (∼9 times the maximal contraction of sham aorta). Furthermore, in vitro incubation of aortas from Wistar and Wistar-Furth rats with aldosterone (10 nmol/l) increased EGF-receptor mRNA expression by >50%. These data indicate that arterial contraction to EGF may occur independent of hypertension and be stimulated by mineralocorticoids.
KW - Hypertension
KW - Vascular smooth muscle contraction
KW - Wistar/Wistar-Furth rats
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U2 - 10.1152/ajpregu.2001.281.3.r878
DO - 10.1152/ajpregu.2001.281.3.r878
M3 - Article
C2 - 11507004
AN - SCOPUS:0034830295
SN - 0363-6119
VL - 281
SP - R878-R886
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 3 50-3
ER -