Decreased hindquarters venous distensibility during high salt intake in stroke-prone spontaneously hypertensive rats.
This study was done to examine whether high salt intake decreases venous distensibility in stroke-prone spontaneously hypertensive rats (SHR-sp). Ten weeks old male SHR-sp and normotensive Wistar-Kyoto rats (WKY) were fed either high (8%) or pressure-volume curves were obtained by infusing Krebs-Henseleit solution retrograde into the inferior vena cava at a rate of 12 or 2.1 ml/min. After 3 weeks of dietary treatment, high salt intake shifted the venous pressure-volume curves at maximal venodilatation caused by nitroprusside toward the pressure axis in SHR-sp but not in WKY. The venous pressure-volume curve during interruption of infusion was also shifted toward the pressure axis in SHR-sp on high salt diet as compared with that in SHR-sp on normal salt diet. Water content and thickness of the smooth muscle layer of the venous wall were not different between the two groups of SHR-sp. These results suggest that high salt intake for 3 weeks decreased hindquarters venous distensibility at maximal venodilatation in SHR-sp but not in WKY. The salt-induced decrease in venous distensibility in SHR-sp might be related to changes in interstitial space compliance or the adventitia since water content or thickness of the smooth muscle layer of the venous wall was not altered.
Ashihara
T
T
Research Institute of Angiocardiology, Kyushu University, Fukuoka, Japan.
Takeshita
A
A
Imaizumi
T
T
Yamamoto
K
K
Hoka
S
S
Nakamura
M
M
D000818:Animals; D002561:Cerebrovascular Disorders / Q000209:etiology; D006614:Hindlimb / Q000098:blood supply; D006973:Hypertension / Q000150:complications / Q000503:physiopathology*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012982:Sodium, Dietary / Q000494:pharmacology*; D013599:Systole; D014680:Veins / Q000187:drug effects* / Q000503:physiopathology
D012982:Sodium, Dietary