Margaret A Hamner

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Stroke incidence increases with age and this has been attributed to vascular factors. We show here that CNS white matter (WM) is intrinsically more vulnerable to ischemic injury in older animals and that the mechanisms of WM injury change as a function of age. The mouse optic nerve was used to study WM function. WM function in older animals (12 months) was(More)
Matrix metalloproteinases (MMPs) and their specific inhibitors the TIMPs play significant roles in angiogenesis. We investigated how the expression of specific MMPs and TIMPs by human microvascular endothelial cells (hmECs) was modulated by culture of the cells in 3-dimensional (3D) type I collagen gels versus 2-dimensional (2D) collagen-coated surfaces. By(More)
UNLABELLED Ischemic preconditioning (IPC) is a robust neuroprotective phenomenon whereby brief ischemic exposure confers tolerance to a subsequent ischemic challenge. IPC has not been studied selectively in CNS white matter (WM), although stroke frequently involves WM. We determined whether IPC is present in WM and, if so, its mechanism. We delivered a(More)
The mammalian central nervous system (CNS) is generally believed to be completely dependent on the presence of oxygen (O(2)) to maintain energy levels necessary for excitability. However, previous studies on CNS white matter (WM) have shown that a large subset of CNS-myelinated axons of mice aged 4 to 6 weeks remains excitable in the absence of O(2). We(More)
OBJECTIVE Hypoglycemia is a common adverse event and can injure central nervous system (CNS) white matter (WM). We determined whether glutamate receptors were involved in hypoglycemic WM injury. METHODS Mouse optic nerves (MON), CNS WM tracts, were maintained at 37°C with oxygenated artificial cerebrospinal fluid (ACSF) containing 10mM glucose. Aglycemia(More)
During angiogenesis, interactions between endothelial cells (ECs) and the surrounding extracellular matrix are influenced by matrix metalloproteinases (MMPs) and their cognate inhibitors, the TIMPs. The authors discovered that the secretion of TIMP-1 by human microvascular ECs (hmECs) cultured within gels of native, fibrillar collagen was increased robustly(More)
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