Professor Pankaj Sah
Pankaj Sah, B.Sc., MBBS, Ph.D. is
Head of Synaptic Plasticity, Queensland Brain Institute at The
University of Queensland, Australia.
He was born in India and moved to Ethiopia for three years before
migrating to Australia with his family. He spent two years in San
Francisco, USA in his first postdoctoral position.
One project in his group is involved with examining the properties of cells in the input side of the amygdala. He has shown that cells within the lateral and basal nuclei can be divided into two broad categories: pyramidal cells and interneurones. Pyramidal cells form the major type of cell (93%) and are similar to excitatory cells found throughout the cortex. The remaining cells (7%) are interneurones which are inhibitory and form extensive connections with the excitatory cells in the amygdala.
Surprisingly Pankaj found that the properties of synaptic inputs onto interneurones were quite different from those onto pyramidal cells. These findings indicate that the modulation of inhibitory pathways may be an important control mechanism within the amygdala. He is now examining the properties of these neurons using a combination of electrophysiological and imaging techniques.
Another project of his is studying the output side of the amygdala the central nucleus. This structure is divided into two main parts, the medial and lateral. It has recently been shown that cells in the lateral division are inhibitory and make local circuits while cells in the medial division project out of the amygdala.
He has been examining the effects of a class of drugs called benzodiazepines (eg diazepam or valium). These drugs are widely used as anxiolytics and their role in the amygdala is of great interest. These drugs are thought to work by potentiating the actions of the major inhibitory transmitter in the brain, gamma amino butyric acid (GABA). He has found that the central nucleus also contains a second type of GABA receptor which is inhibited by benzodiazepines. This finding may have therapeutic implications as a potential target for new classes of drugs.
Pankaj authored Ca2+-activated K+ currents in neurones: types, physiological roles and modulation and coauthored Channels underlying neuronal calcium-activated potassium currents, Apical Dendritic Location of Slow Afterhyperpolarization Current in Hippocampal Pyramidal Neurons: Implications for the Integration of Long-Term Potentiation, Physiological Role of Calcium-Activated Potassium Currents in the Rat Lateral Amygdala, Photolytic Manipulation of [Ca2+]i Reveals Slow Kinetics of Potassium Channels Underlying the Afterhyperpolarization in Hipppocampal Pyramidal Neurons, and Excitatory Synaptic Inputs to Pyramidal Neurons of the Lateral Amygdala.
Pankaj earned his Ph.D. from the John Curtin School of Medical Research for studies of ion channels in neurons in the limbic system.
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