TY - JOUR
T1 - Baroreflex function in females
T2 - Changes with the reproductive cycle and pregnancy
AU - Brooks, Virginia L.
AU - Cassaglia, Priscila A.
AU - Zhao, Ding
AU - Goldman, Robert K.
N1 - Funding Information:
This work was supported in part by grant HL088552 from the National Institutes of Health and by Grant-in-Aid 09GRNT2060630 from the American Heart Association . All authors contributed to the writing of the manuscript and also contributed to the design, conduct, or analysis of aspects of the research from the authors' lab described in this review.
PY - 2012/4
Y1 - 2012/4
N2 - This review briefly describes the changes in baroreflex function that occur during female reproductive life, specifically during the reproductive cycle and pregnancy. The sensitivity or gain of baroreflex control of heart rate and sympathetic activity fluctuates during the reproductive cycle, reaching a peak when gonadal hormone levels increase, during the follicular phase in women and proestrus in rats. The increase in baroreflex sensitivity (BRS) is likely mediated by estrogen because ovariectomy in rats eliminates the BRS increase, the cyclic profile of changes in BRS mirror the changes in estrogen, and estrogen acts in the brainstem to increase BRS. In contrast, pregnancy depresses both BRS and the maximal level of sympathetic activity and heart rate evoked by severe hypotension. The decrease in BRS may be mediated by a reduction in the actions of insulin in the arcuate nucleus to support the baroreflex. In addition, increased levels of the neurosteroid progesterone metabolite 3α-OH-DHP act downstream in the rostral ventrolateral medulla to suppress maximal baroreflex increases in sympathetic activity. Consequently, these changes in baroreflex function impair blood pressure regulation in the presence of hypotensive challenges such as orthostasis and hemorrhage, a common event during delivery. As a result, peripartum hemorrhage is a major cause of human maternal death.
AB - This review briefly describes the changes in baroreflex function that occur during female reproductive life, specifically during the reproductive cycle and pregnancy. The sensitivity or gain of baroreflex control of heart rate and sympathetic activity fluctuates during the reproductive cycle, reaching a peak when gonadal hormone levels increase, during the follicular phase in women and proestrus in rats. The increase in baroreflex sensitivity (BRS) is likely mediated by estrogen because ovariectomy in rats eliminates the BRS increase, the cyclic profile of changes in BRS mirror the changes in estrogen, and estrogen acts in the brainstem to increase BRS. In contrast, pregnancy depresses both BRS and the maximal level of sympathetic activity and heart rate evoked by severe hypotension. The decrease in BRS may be mediated by a reduction in the actions of insulin in the arcuate nucleus to support the baroreflex. In addition, increased levels of the neurosteroid progesterone metabolite 3α-OH-DHP act downstream in the rostral ventrolateral medulla to suppress maximal baroreflex increases in sympathetic activity. Consequently, these changes in baroreflex function impair blood pressure regulation in the presence of hypotensive challenges such as orthostasis and hemorrhage, a common event during delivery. As a result, peripartum hemorrhage is a major cause of human maternal death.
KW - 3α-OH-DHP-baroreflex sensitivity
KW - hemorrhage
KW - insulin
KW - sympathetic nerve activity
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U2 - 10.1016/j.genm.2012.02.004
DO - 10.1016/j.genm.2012.02.004
M3 - Review article
C2 - 22483197
AN - SCOPUS:84859553813
SN - 1550-8579
VL - 9
SP - 61
EP - 67
JO - Gender Medicine
JF - Gender Medicine
IS - 2
ER -