Michael Ziegler, M.D., has done extensive research on sympathetic nervous control of the cardiovascular system, and his work has appeared in over 300 publications. His recent studies have examined how adrenergic genetic polymorphisms alter control of blood pressure in man and transgenic mouse. His NASA research has examined why astronauts lose postural control of blood pressure on their return from space flight, for which he received a NASA award. Dr. Ziegler has chaired several NIH Review Committees and created test drugs to challenge the autonomic activity of astronauts, worked with flight surgeons, helped design protocols to test former astronauts, and worked with NASA to devise current protocols to deal with orthostatic intolerance in astronauts. He is particularly interested in mechanisms that allow the brain to use the sympathetic nervous system to alter physiology.