Sex difference on salt sensitivity and effects of estrogen deficiency on ischemic brain damage through water-free sodium accumulation

2014 Fiscal Year Final Research Report

• Project/Area Number: 24592132
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Cerebral neurosurgery
• Research Institution: 独立行政法人国立病院機構四国こどもとおとなの医療センター(臨床研究部(成育)、臨床研究部(循環器)) (2013-2014); The University of Tokushima (2012)
• Principal Investigator: KANEMATSU Yasuhisa 独立行政法人国立病院機構四国こどもとおとなの医療センター(臨床研究部(成育)、臨, その他部局等, その他 (90363142)
• Co-Investigator(Kenkyū-buntansha): NAGAHIRO Shinji 徳島大学, 大学院ヘルスバイオサイエンス研究部, 教授 (60145315) ; SATOMI Junichiro 徳島大学, 大学院ヘルスバイオサイエンス研究部, 准教授 (10304510)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 脳虚血性疾患 / エストロゲン / 高塩分食 / 組織内Ｎａ貯留

Outline of Final Research Achievements

Estrogen deficiency and hypertension are risk factors for stroke. In ovariectomized (OVX+) rats fed a high-salt diet (HSD), an increase in the body Na+/water ratio was associated with detrimental vascular effects. We hypothesized that an increase in brain water-free Na+ accumulation is associated with ischemic brain damage. The brain Na+/water ratio was increased in OVX+/normal diet (ND) rats as well as in OVX-/HSD and male rats fed HSD. It was augmented in OVX+/HSD rats. Importantly, the increased brain Na+/water ratio before ischemia was positively correlated with the expansion of cortical infarct. Neither OVX+ nor HSD affected the BP in female rats, while HSD increased BP in male rats. Our findings show that an increase in the brain Na+/water ratio elicited by HSD or estrogen deficiency is associated with ischemic brain damage, suggesting the importance of regulating the accumulation of brain water-free Na+

Free Research Field

脳神経外科学