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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Previous exposure to chronic intermittent hypoxia blunts the development of one-kidney, one-clip hypertension in rats

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Author(s):
Perim, Raphael R. [1] ; Amorim, Mateus R. [1] ; Bonagamba, The Late Leni G. H. [1] ; Machado, Benedito H. [1]
Total Authors: 4
Affiliation:
[1] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Physiol, BR-14049900 Ribeirao Preto, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: Experimental Physiology; v. 103, n. 4, p. 473-482, APR 1 2018.
Web of Science Citations: 4
Abstract

Chronic intermittent hypoxia (CIH) and one-kidney, one-clip (1K, 1C) experimental models lead to sympathetic overactivity and hypertension. We hypothesized that previous exposure to CIH potentiates the development of 1K, 1C renal hypertension. Male rats were divided into the following four groups: Control-1K, 1C, maintained under normoxia followed by 1K, 1C surgery (n=19); Control-Sham, maintained under normoxia, followed by sham surgery (n=19); CIH-1K, 1C, exposed to CIH (10days) and 1K, 1C surgery (n=19); and CIH-Sham, exposed to CIH and sham surgery (n=18). Animals were catheterized 8days after 1K, 1C or Sham surgeries and cardiovascular and respiratory parameters recorded on the following day. Baseline mean arterial pressure was higher in Control-1K, 1C than in Control-Sham rats (P<0.05) and was higher in CIH-1K, 1C than in CIH-Sham rats (P<0.05). However, the increase in mean arterial pressure in CIH-1K, 1C animals was significantly blunted in comparison to Con-1K, 1C rats (P<0.05), indicating that previous exposure to CIH attenuates the development of renal hypertension. Systemic administration of hexamethonium, a ganglionic blocker, promoted a larger hypotensive response in Con-1K, 1C compared with CIH-1K, 1C rats (P<0.05), suggesting that sympathetic activity was attenuated in rats previously exposed to the CIH protocol. In addition, removal of the carotid bodies before 1K, 1C renal hypertension eliminated the protective effect of CIH preconditioning on the development of the 1K, 1C hypertension. We conclude that previous exposure to CIH attenuates the development of renal hypertension via a carotid body-dependent mechanism. (AU)

FAPESP's process: 13/06077-5 - Changes in the neural networks involved with the generation and control of sympathetic and respiratory activities in different experimental models of hypoxia
Grantee:Benedito Honorio Machado
Support type: Research Projects - Thematic Grants