Early cerebellar changes after acute hypoxic injury in mice

Abstract

Background and aim: The brain is particularly vulnerable to hypoxia because of its high oxygen consumption. Hypoxia is one of the major pathological events causing neuronal cell injury, neurodegeneration and cell death. The aim of our study was to investigate the early effect of hypoxia on the cerebellar morphology in an experimental mouse model.Material and methods: Mature male ICR mice were subjected to acute hemic hypoxia by a single intraperitoneal injection of NaNO2 at 120 mg/kg body weight. The animals were sacrificed at the 1st and 5th hour after treatment. The cerebellum was excised and processed for histological analysis.Results: Histopathological studies demonstrated changes of the cerebellar Purkinije cells (PC) which were visible even one hour following hypoxia. Along with the intact PC with distinctly stained nucleus, we found shrunken, darkly stained PC with prominent pericellular spaces. Purkinije cells with irregular shape and less strictly aligned were also observed. These changes were more pronounced at the 5th hour following NaNO2 administration. The granular and molecular layers of the cerebellar cortex seemed to be intact.The results demonstrate that Purkinje cells are predominantly affected at the early stage after hypoxic injury.