Research in the Newman laboratory focuses on the physiology of glial cells and on interactions between glia, neurons, and blood vessels in the central nervous system. Glia have traditionally been viewed as passive, housekeeper cells in the brain. This view has been overturned in recent years as studies have demonstrated that glial cells have many essential functions in the CNS and may actively participate in information processing.
The researchers are studying several aspects of glial cell function, including: neuronal activation of glial cells; glial cell modulation of neuronal excitability and synaptic transmission; calcium signaling within and between glial cells; and glial cell regulation of blood flow.
They have demonstrated that astrocytes and Müller cells, the two macroglial cells of the retina, generate both spontaneous and neuron-evoked calcium signals. These calcium signals, in turn, lead to the release of transmitters from glial cells, resulting in the modulation of neuronal excitability. The group is currently studying how these glial signals affect information processing in the retina. They are also studying how pathology affects glial calcium signaling.
The group has shown that factors released from glial cells regulate blood flow in the retina. Light stimulation or direct activation of glial cells results in the release of arachidonic acid metabolites. Some of these metabolites constrict while others dilate vessels. The researchers are studying how glia to vessel signaling is modulated and the role that glial cells play in controlling blood flow.