High salt diet enhances cardiovascular responses from the nucleus tractus solitarius and ventrolateral medulla of Sprague-Dawley rats.
Clin Exp Hypertens
; 27(1): 33-44, 2005 Jan.
Article
in En
| MEDLINE
| ID: mdl-15773228
ABSTRACT
High salt intake has been shown to augment the sensitivity of rostral ventrolateral medulla (RVLM) sympathoexcitatory neurons. We examined the effects of 4 weeks of high dietary salt (8%) on the sensitivity of nucleus tractus solitarius (NTS) and caudal ventrolateral medulla (CVLM) in controlling RVLM. In chloralose-anesthetized Sprague-Dawley rats, high salt intake did not elevate baseline arterial pressure or heart rate (HR). In high-salt group, NTS, CVLM, and RVLM responses to glutamate were greater. NTS responses to acetylcholine or serotonin, which is independent of baroreflex, also were greater. Phenylephrine or nitroprusside (i.v.) elicited similar changes in arterial pressure and heart rate, the baroreflex sensitivity also was similar in both groups of rats. These results suggest that high salt intake augments the sensitivity of NTS and CVLM sending inhibitory input to RVLM. This presumably may inhibit the RVLM, thereby inhibiting the elevation of arterial pressure.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Medulla Oblongata
/
Solitary Nucleus
/
Sodium Chloride, Dietary
/
Hypertension
Limits:
Animals
Language:
En
Journal:
Clin Exp Hypertens
Year:
2005
Document type:
Article
Affiliation country:
Japón