Dr. Michael Morgan
Courses
| Course ID | Title | Meeting Time | Location | Semester | Syllabus |
|---|---|---|---|---|---|
| Psych 312 | Experimental Methods in Psychology | Tu,Th 2:50-5:30 | VUCB 222 | Fall 2011 | |
| Psych 401 | Historical Development of Psychology | Tu,Th 12:00 - 1:15 | VUCB 222 | Fall 2011 |
Research
Neural Mechanisms of Morphine Tolerance
Opiates such as morphine are the most effective treatment for pain. Unfortunately, the ability of opioids to relieve pain is reduced with repeated administration. The primary goal of our research is to determine the mechanism for tolerance so long lasting and effective pain treatments can be developed. Our research has shown that tolerance occurs by a change in opioid sensitive GABAergic neurons in the ventrolateral region of the periaqueductal gray (PAG). Injection of opioids into this brain region produces analgesia and repeated injections results in tolerance. We are currently examining the role of mu-opioid receptor internalization in morphine tolerance. These studies indicate that repeated administration of morphine increases the likelihood that the mu-opioid receptor will internalize which produces tolerance by limiting membrane signaling.
Current Funding:
Morgan, M. M., Aicher, S.A. (co-P.I), & Ingram, S. L. (co-P.I). National Institute on Drug Abuse. Psychostimulants Induce Long-Term Changes in Nociception (R01 DA027625). September 2009 to July 2014. $1,625,000 direct costs.
Morgan, M. M. & Ingram, S. L. (co-P.I) National Institute on Drug Abuse. Cellular mechanisms of opioid tolerance. (RO1 DA015498-06). August 2009 to July 2011. $450,000 direct costs.
Morgan, M. M. National Institute on Drug Abuse. Neural Mechanisms of Enhanced Cannabinoid/Opioid Antinociception. (R03 DA026591). May, 2009 to April, 2011. $100,000 direct costs.
Graduate Students
Michelle Cyr, Psychology, Ph.D. 2011
Adie Wilson, Neuroscience, PhD. 2011
Erin Bobeck, Psychology
Melissa Mehalick, Psychology
Kimber Saville, Psychology
Recent Publications
Cornélio, A.M., Mendes-Gomes, J., Fugimoto, J.S., Morgan, M.M., & Nunes-de-Souza, R.L. (in press) Environmentally induced antinociception and hyperalgesia in rats and mice. Brain Research.
Morgan, M. M. & Christie, M. J. (in press) Analysis of Opioid Efficacy, Tolerance, Addiction, and Dependence from Cell Culture to Human. British Journal of Pharmacology.
Gunn, A., Bobeck, E.N., Weber, C., & Morgan, M.M. (2011). The influence of non-nociceptive factors on hot plate latency in rats. Journal of Pain, 12:222-227.
Fyfe LW, Cleary DR, Macey TA, Morgan MM, Ingram SL. (2010). Tolerance to the antinociceptive effect of morphine in the absence of acute presynaptic desensitization in rat periaqueductal gray neurons. J Pharmacol Exp Ther. 335(3):674-80. PMID: 20739455
Macey T. A., Ingram, S. L., Bobeck, . N., Hegarty, D. M., Aicher, S. A., , S. & Morgan, M. M. (2010). Opioid receptor internalization contributes to dermorphin-mediated antinociception. Neuroscience, 168:543-50. PMID: 20394808
Bobeck, E.N., McNeal, A.L. & Morgan, M.M. (2009) Drug dependent sex differences in periaqueductal gray mediated antinociception in the rat. Pain, 147:210-216. PMID: 19796879
Macey, T.A., Bobeck, E.N., Hegarty, D.H., Aicher, S.A., Ingram,S.L., & Morgan, M.M. (2009). Extracellular signal-regulated kinase 1/2 activation counteracts morphine tolerance in the periaqueductal gray of the rat. The Journal of Pharmacology and Experimental Therapeutics, 331:412-8. PMID: 19684256
Morgan, M. M. Bobeck, E. N., & Ingram, S. L. (2009). Glutamate Modulation of Antinociception, but not Tolerance Produced by Morphine Microinjection into the Periaqueductal Gray of the Rat. Brain Research, 1295: 59-66. PMID: 19664608
Cyr, M.C. & Morgan, M.M. (2009). Early Methylphenidate Exposure Enhances Morphine Antinociception and Tolerance in Adult Rats. Neuropharmacology, 7:673-677. PMID: 19646456
Meyer, P.J., Morgan, M.M., Kozell, L.B., & Ingram, S.L. (2009). Contribution of dopamine receptors to periaqueductal gray-mediated antinociception. Psychopharmacology, 204(3):531-40. PMID: 19225762
Morgan, M. M., Ashley, M. D., Ingram, S. L., & Christie, M. (2009). Behavioral consequences of chronic morphine-induced delta receptor upregulation in the periaqueductal gray of the rat. Neural Plasticity, 2009:516328. PMID: 19266049
Education
- Ph.D. 1989 UCLA Physiological Psychology (J.C. Liebeskind mentor)
- Post-doctoral fellow 1989 - 1993 Dept. of Neurology, UC, San Francisco (H.L. Fields mentor)