Effect of Experimental Cerebral Infarction on Heart Rate Variability in Rats

Objective To investigate the effect of acute cerebral infarction on cardiac autonomic nervous activity.Methods A total of 32 Wistar rats were divided into normal group,sham operation group and infarction group by random.Experimental cerebral infarction in Wistar rats was induced by intraluminal occlusion of middle cerebral artery.About 24 hours after the occlusion or 24 hours after sham operation,the heart rate variability(HRV) sequences were measured,and the HRV values in the three groups were compared.The levels of catecholamine and neuropeptide(NPY) in myocardium were measured.Results At the 24th hour after the occlusion,the standard deviation and root mean square standard deviation of R-R interval,the total power,high frequency(HF) and low frequency(LF) in infarction group were lower than those in normal and sham operation group.LF/HF and fractal dimension did not differ much among the three groups.The levels of noradrenaline and NPY in myocardium in infarction group were higher than those in the other groups.Conclusion It is suggested that acute cerebral infarction may cause the decrease of autonomic nervous activity and damage of the autonomic nervous function;the abnormal secretion of noradrenalin in autonomic nerve ending and NPY may be the important reasons.