Microcirculation of the epimyocardial layer of the rat heart: no recruitment after hypoxia.
1. In vivo microscopic studies of the microcirculation of the beating mammalian heart are accomplished by use of small needles connected to the operation table, restricting excessive movement of the cardiac surface. 2. Fluorescence microscopic techniques combined with a highly sensitive TV tape system, enable to determine microvascular diameters, intercapillary distances, as well as directions and velocities of capillary flow in the epimyocardial layer of the mammalian heart. 3. During acute hypoxia, no recruitment of previously resting capillaries could be observed. 4. The capillary flow pattern of the epimyocardial layer reveals a mixed countercurrent system.
D000818:Animals; D001160:Arterioles / Q000503:physiopathology; D002196:Capillaries / Q000503:physiopathology; D006321:Heart / Q000503:physiopathology*; D000860:Hypoxia / Q000097:blood*; D008833:Microcirculation; D051381:Rats; D014699:Venules / Q000503:physiopathology