Abstract
Careful regulation of cerebral blood flow is required to maintain proper brain function. The cerebral arteries are particularly sensitive to the effects of hypertension, which alters the arteries in a manner that impairs the brains ability to tightly regulate perfusion. This chapter focuses the effects of hypertension on cerebral artery structure and function, with emphasis on myogenic reactivity and endotheliumdependent dilation. Hypertension causes a reduction in the lumen diameter of cerebral arteries and this is often associated with an increase in the wall-to-lumen ratio. Several circulating factors have been implicated in mediating this inward artery remodeling; these include aldosterone, angiotensin II, proinflammatory cytokines, and reactive oxygen species. Endothelium-dependent dilation in response to nitric oxide and epoxyeicosatrienoic acids is impaired in hypertension; this leads to increases in myogenic tone and impaired dilation. Dysfunction of ion channels, including calcium-activated potassium channels and transient receptor potential (TRP) V4 channels, has also been associated with impaired endothelial function in hypertensive models. Understanding the mechanisms responsible for the hypertension- associated vascular dysfunction is important because hypertension is associated with an increased risk of dementia and stroke and with increased ischemic injury in the event of a stroke.
Original language | English (US) |
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Title of host publication | Hypertension and the Brain as an End-Organ Target |
Publisher | Springer International Publishing |
Pages | 99-134 |
Number of pages | 36 |
ISBN (Electronic) | 9783319256160 |
ISBN (Print) | 9783319256146 |
DOIs | |
State | Published - Jan 1 2016 |
Externally published | Yes |
Keywords
- Arterial remodeling
- Autoregulation
- Cerebral artery
- Cerebral blood flow
- Hypertension
- Neuromuscular coupling
ASJC Scopus subject areas
- General Medicine
- General Neuroscience