| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Dalton Cardiovascular Research Center, University Of Missouri, Columbia, MO, USA
2 Department of Veterinary Biomedical Sciences, University of Missouri, Columbia, MO, USA
3 Department of Biochemistry and Child Health, University of Missouri, Columbia, MO, USA; MU Center for Phytonutrient and Phytochemical Studies, University of Missouri, Columbia, MO, USA
4 Dalton Cardiovascular Research Center, University Of Missouri, Columbia, MO, USA; Department of Veterinary Biomedical Sciences, University of Missouri, Columbia, MO, USA
* To whom correspondence should be addressed. E-mail: PamidimukkalaJ{at}missouri.edu.
It has been suggested that estrogen modulates baroreflex regulation of autonomic function. The present study evaluated the effects of estrogen on baroreflex regulation of heart rate in response to changes in blood pressure with phenylephrine (PE), angiotensin II (AngII) and sodium nitroprusside (SNP) in a conscious mouse model. Males and ovariectomized females with (OvxE+) and without (OvxE-) estradiol replacement, chronically implanted with arterial and venous catheters were used in these studies. The slope of the baroreflex bradycardic responses to PE was significantly facilitated in OvxE+ females (-7.65±1.37) compared to OvxE- females (-4.5±0.4). Likewise, the slope of the baroreflex bradycardic responses to AngII was significantly facilitated in OvxE+ females (-7.97±1.06) compared to OvxE- females (-4.8±1.6). Reflex tachycardic responses to SNP were comparable in all the groups. Lastly, in male mice, the slope of AngII induced baroreflex bradycardia (-5.17±0.95) was significantly less than that induced by PE (-8.50±0.92), but this AngII mediated attenuation of reflex bradycardia was not observed in the female mice. These data support the hypothesis that estrogen facilitates baroreflex function in female mice and suggest that AngII mediated acute blunting of baroreflex regulation of heart rate may be sex dependent.
This article has been cited by other articles:
|
|
 |
|
  H. Girouard, A. Lessard, C. Capone, T. A. Milner, and C. Iadecola The neurovascular dysfunction induced by angiotensin II in the mouse neocortex is sexually dimorphic Am J Physiol Heart Circ Physiol, January 1, 2008; 294(1): H156 - H163. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. G. Krause, K. S. Curtis, J. P. Markle, and R. J. Contreras Oestrogen affects the cardiovascular and central responses to isoproterenol of female rats J. Physiol., July 1, 2007; 582(1): 435 - 447. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. M. Wenner, A. V. Prettyman, R. E. Maser, and W. B. Farquhar Preserved autonomic function in amenorrheic athletes J Appl Physiol, August 1, 2006; 101(2): 590 - 597. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Xue, J. Pamidimukkala, and M. Hay Sex differences in the development of angiotensin II-induced hypertension in conscious mice Am J Physiol Heart Circ Physiol, May 1, 2005; 288(5): H2177 - H2184. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Pamidimukkala, B. Xue, L. G. Newton, D. B. Lubahn, and M. Hay Estrogen receptor-{alpha} mediates estrogen facilitation of baroreflex heart rate responses in conscious mice Am J Physiol Heart Circ Physiol, March 1, 2005; 288(3): H1063 - H1070. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. J. Harvey, B. L. Morris, J. A. Miller, and J. S. Floras Estradiol Induces Discordant Angiotensin and Blood Pressure Responses to Orthostasis in Healthy Postmenopausal Women Hypertension, March 1, 2005; 45(3): 399 - 405. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
