Repercusiones autonómicas y metabólicas en un modelo experimental de isquemia cerebral global y focal
Introduction. During the last decades the influence of cerebrovascular disease on heart and autonomic nervous system has been studied in numerous reports. Autonomic and methabolic changes have been described during brain ischemia. Methods. We studied some parameters and its modifications during global (GBI) and focal brain ischemia (FBI). Ten Wistar rats were subjected to global ischemia and eleven to focal brain ischemia, during 20 and 90 minutes followed in both cases by reperfussion. Mean blood pressure, heart rate and glycaemia before, during and after brain ischemia were registered. pH, pO2 and pCO2 were maintained within normal range using endovenous tamponed solutions. Results. During GBI the blood pressure rose and returned to normal in the reperfussion period. Heart rate decreased in both stroke models and hyperglycaemia was present from the beginning in two groups. Conclusions. GBI and FBI bring about autonomic changes as increased mean blood pressure (only in GBI) and decreased heart rate; probably these might be explained by an autonomic nervous system disorder or by intracranial hypertension. Hyperglycaemia could be related to cathecholamines secretion. These effects might influence in the pathophysiology of brain ischemia
Resultados Durante la ICG la presión arterial se elevó, retornando a sus valores normales en el período de reperfusión. En ambos modelos de isquemia se observó un descenso de la frecuencia cardíaca y, por otra parte, hiperglucemia que se mantuvo en la fase de reperfusión.
Conclusiones Nuestros resultados apoyan que la isquemia cerebral global y la isquemia focal inducen cambios como elevación de la presión arterial (sólo en ICG) y disminución de la frecuencia cardíaca, que pueden ser secundarias a una disregulación del SNA o hipertensión intracraneal, e hiperglucemia en probable relación a la secreción de catecolaminas. Estos efectos podrían influir en la fisiopatología de la isquemia cerebral