Estrogen replacement suppresses pressor response and oxidative stress induced by cage-switch stress in ovariectomized rats.
We examined the suppressive effects of estradiol on psychological stress-induced cardiovascular responses and oxidative stress in ovariectomized rats, both placebo-treated (OVX+Pla) and estrogen-treated (OVX+E2). The elevations in blood pressure and heart rate induced by cage-switch stress were attenuated in the OVX+E2 as compared with the OVX+Pla group. N(G)-nitro-L-arginine methyl ester, administered via drinking water, reduced the difference in these responses. Furthermore, this stress increased plasma nitrotyrosine and decreased plasma nitric oxide (NO) metabolites only in the OVX+Pla group. We demonstrated that estrogen replacement suppresses cardiovascular responses to psychological stress, at least in part by improving NO bioavailability in ovariectomized rats.
Morimoto
Keiko
K
Department of Environmental Health, Faculty of Life Science and Human Technology, Nara Women's University, Nara, Japan. kmorimot@cc.nara-wu.ac.jp
Uji
Masami
M
Ueyama
Takashi
T
Kimura
Hiroko
H
Kohno
Tomomi
T
Takamata
Akira
A
Yano
Shigenobu
S
Yoshida
Ken-ichi
K
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006799:Housing, Animal; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D010052:Ovariectomy; D018384:Oxidative Stress / Q000187:drug effects*; D010919:Placebos; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000188:drug therapy; D014443:Tyrosine / Q000031:analogs & derivatives / Q000097:blood
D004791:Enzyme Inhibitors; D004967:Estrogens; D010919:Placebos; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D019331:NG-Nitroarginine Methyl Ester