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Search Program Faculty/Research

William Clarke, Ph.D.

Clarke photo


Research in Dr. William Clarke's lab is focused on understanding the molecular mechanisms that underlie drug efficacy (the ability of a drug to produce a response) and its regulation. 

We study the behavioral effects and cellular signaling profiles of opioid agonists (e.g. morphine) that act on peripheral pain-sensing neurons that reside outside the CNS. Peripheral pain-sensing neurons sense actual or potential tissue damage and send signals into the CNS that are interpreted as pain. 

Drugs that target opioid receptors expressed by these sensory neurons have the potential to inhibit neuronal signaling and reduce pain neurotransmission. Thus, peripherally-restricted opioid drugs would be effective analgesics, but would be devoid of debilitating and life-threatening CNS-mediated adverse effects (e.g. respiratory depression, addiction, etc.) that plague current opioid analgesics.

Selected Publications

Clarke WP, Chavera TA, Silva M, Sullivan LC, Berg KA. Signalling profile differences: paliperidone versus risperidone. Br J Pharmacol. 2013 Oct;170(3):532-45.

Berg KA, Rowan MP, Gupta A, Sanchez TA, Silva M, Gomes I, McGuire BA, Portoghese PS, Hargreaves KM, Devi LA, Clarke WP. Allosteric interactions between δ and κ opioid receptors in peripheral sensory neurons. Mol Pharmacol. 2012 Feb;81(2):264-72.

Berg KA, Rowan MP, Sanchez TA, Silva M, Patwardhan AM, Milam SB, Hargreaves KM, Clarke WP. Regulation of κ-opioid receptor signaling in peripheral sensory neurons in vitro and in vivo. J Pharmacol Exp Ther. 2011 Jul;338(1):92-9.

Clarke WP, Berg KA. Use of functional assays to detect and quantify functional selectivity. Drug Discovery Today: Technologies. 7: e31-e36, 2010.

Berg KA, Maayani S, Goldfarb J, Scaramellini C, Leff P, Clarke WP. Effector pathway-dependent relative efficacy at serotonin type 2A and 2C receptors: evidence for agonist-directed trafficking of receptor stimulus. Mol Pharmacol. 1998 Jul;54(1):94-104.



Ph.D., Physiology, Wayne State University School of Medicine, 1984

M.S., Biology, Northeastern University, 1979

B.S., Chemistry, Boston College, 1974



Phone: (210) 567-4171

Research Profile
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