β-adrenergic Receptor Signaling In Normal And Hypoxic Mature And Immature Guinea-pig Myocardium Undergoing Global Ischemic-reperfusion

Myocardial ischemic-reperfusion injury, playing a notable role in preventing the patients undergoing heart operation from better recovery, is certainly an important factor impeding the development of cardiac surgery. Therefore attention has been payed to what is responsible for ischemic-reperfusion injury and how to attenuat the injury. It has been understood that immature myocardium differs from mature one in such as morphology, cardiac function, metabolism and so forth. So does hypoxic or cyanotic myocardium from normal one. Nowaday, research on cell signaling leads the investigation in the medical and pharmological field. Myocardial β-adrenergic receptor (β AR)-guanine nucleotide-binding protein (G protein)-adenylate cyclase (AC) complex, a primary signaling system in the heart, is closely associated with cardiac function. Abnormalities of this system are thought to exit in myocardial ischemic-reperfusion, which affects the recovery of cardiac function. Really, this is a new view in the realm of study about myocardial ischemic-reperfusion with a bright future. As far as we know, it has been few reported on the different alteration of the system between normal and hypoxic or cyanotic mature and immature myocardium, and on the different effects of a variety of commonly applied myocardial protection means in clinic on the system. In the present study, isolated perfused working heart preparation and normobaric hypoxic guenia-pig model were established. Cardiac functions, myocardial content of adenosine triphosphate (ATP) and creatine phosphate (CP), myocardial structure under light or electron microscope and the changes of...