The Science Seminar Series:November 5, 2009
How ion channels set the rhythm in pituitary cells
Dr. Joel Tabak, Assistant Scholar/Scientist
Department of Biological Science
Florida State University.
Time: 4:00 -5:00pm
Neurons and many endocrine cells exhibit electrical activity. In response to a stimulus, or spontaneously, the potential across the cell membrane can rapidly increase by more than 50 mV and then rapidly decrease back to its resting level. During such an event – called action potential – calcium ions enter the cell and trigger various cellular actions such as hormone release. Cells often fire periodic bursts of action potential that lead to large calcium influx. This electrical activity is the result of differences in ionic concentration across the cell membrane and membrane potential variations occur when ions cross the membrane through ion channels. Sodium and calcium ions enter the cell and therefore raise the membrane potential, while potassium channels exit the cell, decreasing membrane potential. In this talk I will show how interactions between calcium and potassium ion channels create patterns of electrical activity in endocrine cells of the pituitary gland.