Adaptive changes in heart during acclimation to hypoxia in the rat
- VernacularTitle:低氧习服过程中大鼠心脏的适应性改变
- Author:
Qingyuan HUANG
;
Yuqi GAO
;
Jingquan SHI
;
Fuyu LIU
;
Jian CHEN
;
Lifei CAO
;
Bingyon SUN
- Publication Type:Journal Article
- Keywords:
Anoxia;
Neovascularization;
Heart;
Acclimatization
- From:
Chinese Journal of Pathophysiology
2000;0(07):-
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To study the changes in myocardial blood flow (MBF), capillarization and cardiac function in the rat during acclimation to hypoxia. METHODS: Myocardial capillary density (CD) and capillary/myocyte ratio (C/M) was assayed by alkaline phosphatase histochemistry. Biomicrosphere method was used to determine MBF in the rat after 5, 15 or 30 days hypobaric hypoxic exposure (5 000 m). RESULTS: In the course of hypoxia, MBF and cardiac function increased in the right ventricle. However, in the left ventricle, acute hypoxia caused an increase in MBF and a decrease in cardiac function. Both returned to the control level on continued hypoxic exposure. Neovascularization occurred after 15 day or 30 day of hypoxic exposure in both ventricles, judged from the significant increment of C/M ratio albeit the CD remained unchanged in the right ventricle. CONCLUSION: Our findings indicate that adaptive changes in rat heart during acclimation to hypoxia include: ① persistent increase in MBF, hypertrophy associated with increase in capillarity and enhanced cardiac function of the right ventricle; ② increase in MBF and depression of cardiac function at first, then followed by recovery of MBF and increase in capillarity accompanied with recovery of left ventricular function.
