Phone: (205) 934-3523
E-mail: mcmahon@uab.edu

Research/Clinical Interest Description: My laboratory has three major areas of investigation: First, we are investigating the mechanisms by which muscarinic and adrenergic receptors modulate synaptic function and plasticity in hippocampus and visual cortex. In addition, we are pursuing the consequences of lesion of the cholinergic and adrenergic inputs to hippocampus and visual cortex on the ability of synapses to express plasticity. Degeneration of cholinergic and adrenergic innervation that occurs in neurodegenerative diseases and aging is known to cause cognitive deficits, thus determining how synaptic function is altered following loss of these inputs could have significant clinical benefit. In a second project, we are pursuing the effects of estradiol on hippocampal synapse density and synaptic transmission and plasticity. We are particularly interested in determining how loss of estradiol during aging impacts hippocampal function and whether hormone replacement therapy can activate estradiol-dependent mechanisms to restore normal hippocampal function and thus learning and memory. In a third project, we are investigating the characteristics of glycine-gated chloride channels in mammalian hippocampus and the functional role these channels play in mediating novel mechanisms of neuronal inhibition. In addition, we are investigating the ability of these channels to both interrupt and prevent seizure activity in hippocampus with the goal of demonstrating that these channels could be a novel target for the development of antiepileptic therapy. We employ electrophysiological recordings of neurons in acutely prepared brain slices combined with behavioral assays, pharmacology, biochemistry, morphology and immunohistochemistry to pursue our goals.