Adaptations in autonomic nervous system regulation in normal and hypertensive pregnancy

Virginia L. Brooks, Qi Fu, Zhigang Shi, Cheryl M. Heesch

Research output: Chapter in Book/Report/Conference proceedingChapter

1 Scopus citations

Abstract

There is an increase in basal sympathetic nerve activity (SNA) during normal pregnancy; this counteracts profound primary vasodilation. However, pregnancy also impairs baroreflex control of heart rate and SNA, contributing to increased mortality secondary to peripartum hemorrhage. Pregnancy-induced hypertensive disorders evoke even greater elevations in SNA, which likely contribute to the hypertension. Information concerning mechanisms is limited. In normal pregnancy, increased angiotensin II acts centrally to support elevated SNA. Hypothalamic sites, including the subfornical organ, paraventricular nucleus, and arcuate nucleus, are likely (but unproven) targets. Moreover, no definitive mechanisms for exaggerated sympathoexcitation in hypertensive pregnancy have been identified. In addition, normal pregnancy increases gamma aminobutyric acid inhibition of the rostral ventrolateral medulla (RVLM), a key brainstem site that transmits excitatory inputs to spinal sympathetic preganglionic neurons. Accumulated evidence supports a major role for locally increased production and actions of the neurosteroid allopregnanolone as one mechanism. A consequence is suppression of baroreflex function, but increased basal SNA indicates that excitatory influences predominate in the RVLM. However, many questions remain regarding other sites and factors that support increased SNA during normal pregnancy and, more importantly, the mechanisms underlying excessive sympathoexcitation in life-threatening hypertensive pregnancy disorders such as preeclampsia.

Original languageEnglish (US)
Title of host publicationHandbook of Clinical Neurology
PublisherElsevier B.V.
Pages57-84
Number of pages28
DOIs
StatePublished - 2020

Publication series

NameHandbook of Clinical Neurology
Volume171
ISSN (Print)0072-9752
ISSN (Electronic)2212-4152

Keywords

  • Angiotensin II
  • Heart rate
  • Hypothalamus
  • Preeclampsia
  • Pregnancy
  • Sympathetic nerve activity

ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology

Fingerprint Dive into the research topics of 'Adaptations in autonomic nervous system regulation in normal and hypertensive pregnancy'. Together they form a unique fingerprint.

Cite this