Ralph Lydic, Ph.D.  ~Professor of Molecular and Integrative Physiology ~Professor, Department of Anesthesiology 7433 Medical Science I 0615 (734) 647-7831 rlydic@umich.edu

Current Research: 

Ralph Lydic, PhD., is the Bert La Du Professor of Anesthesiology, Professor of Physiology, and Associate Chair Anesthesia Research. The National Heart, Lung, and Blood Institute of the National Institutes of Health funds Dr. Lydic's laboratory. The goals of his research programs are to elucidate the mechanisms by which sleep, opioids, and volatile anesthetics depress breathing and arousal. The evolutionary perspective, and current data, supports the view that neurons generating sleep and wakefulness preferentially modulate the ability of opioids, hypnotics, and anesthetics to obtund wakefulness. This concept underlies work in Dr. Lydic's laboratory characterizing the neurochemical and signal transduction processes through which cholinergic neurons modulate sleep, arousal, and autonomic control. Recent work has shown that adenosine and nitric oxide modulate pontine acetylcholine release and arousal. A second research program is characterizing the effects of opioids on cholinergic neurotransmission. These studies aim to understand the cellular and molecular mechanisms by which opioids inhibit cholinergic neurotransmission and disrupt sleep and breathing. Both of these research programs encourage an active interaction between basic and clinical investigators.

Representative Publications:

Douglas CL, Bowman, GN, Baghdoyan HA, and Lydic R. C57BL/6J and
B6.V-LEPOB mice differ in the cholinergic modulation of sleep and
breathing. J App Physiol 98:918-929, 2005.

Lydic R. Performance-enhancing drugs present a double-edge sword. APSF
Newsletter, pg 5, Spring 2005 .

Lydic R and Baghdoyan HA. Sleep, anesthesiology, and the neurobiology
of arousal state control. Anesthesiology 103: 1268-95, 2005.

Osman NI, Baghdoyan HA, Lydic R. Morphine inhibits acetylcholine
release in rat prefrontal cortex when delivered systemically or by
microdialysis to basal forebrain. Anesthesiology 103: 779-87, 2005.

Lydic R and Baghdoyan HA. Sleep and anesthesia. In: Foundations of
Anesthesia: Basic and Clinical Sciences, 2 nd Edition Edited by H.C.
Hemmings and P.M. Hopkins. 361-371, 2005.

Bernard R, Lydic R, and Baghdoyan HA. Hypocretin receptor-activated G
proteins revealed by [ 35S]GTP g S autoradiography. In: The
Orexin/Hypocretin System: Physiology and Pathophysiology. Editors: S.
Nishino and Takeshi Sakurai. 83-96, 2006 .

Bernard R, Lydic R, Baghdoyan HA. Hypocretin (orexin) receptor subtypes
differentially enhance acetylcholine release and activate G protein
subtypes in rat pontine reticular formation. J Pharmacol Exp Ther
317:163-171, 2006.

Lydic R and Baghdoyan HA. Relevance of anesthesiology for sleep
medicine. In: Encyclopedia of Sleep Medicine. Edited by T. Lee-Chiong.
927-932, 2006.

Lydic R, Garza-Grande R, Struthers R, Baghdoyan HA. Nitric oxide in B6
mouse and nitric oxide-sensitive soluble guanylate cyclase in cat
modulate acetylcholine release in pontine reticular formation. J Appl
Physiol 100:1666-1673, 2006.

Coleman CG, Baghdoyan HA, Lydic R. Dialysis delivery of an adenosine
A2A agonist into the pontine reticular formation of C57BL/6J mouse
increase pontine acetylcholine release and sleep. J Neurochem
96:1750-1759, 2006.

Lydic R. Sleep disruption is related to allelic variation in the ob
gene. Am J Physiol Regul Integr Comp Physiol 290:R892-893, 2006.

Lydic R. and H.A. Baghdoyan. Acetylcholine modulates sleep and
wakefulness: A synaptic perspective. In: The Neurochemistry of Sleep and
Wakefulness. Edited by J.M. Monti, S.R. Pandi-Perumal, and C.M. Sinton.
Cambridge University Press, (in press) 2007.

Lydic R and HA Baghdoyan. Neurochemical mechanisms mediating
opioid-induced REM sleep disruption. In: Sleep and Pain, edited by G.
Lavigne, M. Choinière, B.J. Sessle, and P. Soja. Seattle : International
Association for the Study of Pain (in press) 2007.

Watson CJ, Lydic R, Baghdoyan HA. Sleep and GABA levels in the oral
part of rat pontine reticular formation are decreased by local and
systemic administration of morphine. Neuroscience 144:375-86, 2007.

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