Abstract TP90: Disruption of Connexin30/32 Contributes to Impaired oligodendrogenesis in Ischemic White Matter Injury

Hypothesis: Astrocytes expressing connexin (Cx) 30 forms gap junctions with oligodendrocytes expressing Cx32. Gap junctions are the molecular basis for the panglial syncytium and are vital for oligodendrocyte survival as well as white matter integrity. Disruption of astrocyte-oligodendrocyte (A/O) gap junctions has been shown in several demyelinating central nervous system disorders. However, their involvement in cerebral ischemia remains largely unknown. Methods: Ischemic white matter injury in mice was induced by long-term bilateral carotid artery sclerosis (BCAS). White matter injury was examined by MBP staining and 7T-MRI. Cognitive impairment of BCAS mice was assessed by Novel object recognition and Morris water maze test. Expression of connexin30 and connexin32 in astrocytes and oligodendrocytes, respectively, was measured by real-time PCR and immunofluorescence. Brdu was used to label pre-oligodendrocytes and newly generated oligodenrocytes. Oligodendrogenesis was calculated by the ratio of newly g...