Role of the medulla oblongata in hypertension.
Hypertension
; 38(3 Pt 2): 549-54, 2001 Sep.
Article
em En
| MEDLINE
| ID: mdl-11566929
Brain pathways controlling arterial pressure are distributed throughout the neuraxis and are organized in topographically selective networks. In this brief review, we will focus on the medulla oblongata. The nucleus tractus solitarius (NTS) is the primary site of cardiorespiratory reflex integration. It is well accepted that lesions or other perturbations in the NTS can result in elevations of arterial pressure (AP), with many of the associated features so commonly found in humans. However, recent studies have shown 2 distinct subpopulations of neurons within the NTS that can influence AP in opposite ways. Commissural NTS neurons located on the midline may contribute to maintenance of hypertension in spontaneously hypertensive rats (SHR), because small lesions in this area result in a very significant reduction in AP. Also involved in this blood pressure regulation network are 2 distinct regions of the ventrolateral medulla: caudal (CVLM) and rostral (RVLM). Neurons in CVLM are thought to receive baroreceptor input and to relay rostrally to control the activity of the RVLM. Projections from CVLM to RVLM are inhibitory, and a lack of their activity may contribute to development of hypertension. The RVLM is critical to the tonic and reflexive regulation of AP. In different experimental models of hypertension, RVLM neurons receive significantly more excitatory inputs. This results in enhanced sympathetic neuronal activity, which is essential for the development and maintenance of the hypertension.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bulbo
/
Hipertensão
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Hypertension
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos