OHSU

Ronnie Dhaher

Ph.D. Graduate (2007)

Ronnie DhaherUndergraduate Education

B.S. University of California, Santa Barbara (Pharmacology & Biopsychology) 1998-2000
A.S. Monterey Peninsula Community College (Pre-pharmacy) 1995 - 1997  

Training at OHSU

2000-2007

Second Year Project

The extended amygdala and ethanol reward
Mentor: Robert Hitzemann, PhD

Dissertation

Determining the role of the extended amygdala in regulating alcohol consumption in C57Bl/6J (B6) mice
Mentors: Robert Hitzemann, PhD & Deborah Finn, PhD

Previous Career Positions

09/2010 – 09/2012: Postdoctoral Associate, Department of Laboratory Medicine Yale University
10/2007 – 08/2010: Postdoctoral Fellow, Department of Psychiatry  Indiana University Purdue University of Indianapolis

Current Career Position

9/01/2012 to Present: Associate Research Scientist, Department of Laboratory Medicine, Yale University

E-mail Address

roni.dhaher@yale.edu

Undergraduate and Graduate Student Research Background

I received my Bachelors of Science in Pharmacology and Biopsychology from the University of California in Santa Barbara.  At the time, a big influence on my research thinking stemmed from my undergraduate pharmacology laboratory courses; specifically, the classic tissue bath experiments, where the contractile properties of smooth muscle (guinea pig ileum and rabbit jujunum) and cardiac muscle (guinea pig heart) could be dose dependently altered and augmented by autonomic neurotransmitters and pharmacological agents.  To me, this was very powerful in demonstrating the ability of chemicals to affect biological systems.  My undergraduate research project involved pharmacologically manipulating the contractility of the ovarian smooth muscle of rockfish genus Sebastes.  The goal of the experiments carried out in the rockfish was to find a way to inhibit the contraction of the ovarian wall (which in the rockfish also acts as a uterus) so as to prevent premature birth and increase the survival rate of the offspring. 

For graduate school, I chose to attend the Behavioral Neuroscience program at Oregon Health & Sciences University because I wanted to study the neurochemistry of behavior.  I wanted to progress from studying the ability of drugs injected into a tissue bath to contract smooth muscle, to studying the ability of drugs microinjected into a specific brain region to affect behavior.  During first year lab rotations, I played a role in experiments where I pharmacologically manipulated regions of the brain reward circuit to affect behaviors sensitive to drugs of abuse.  For example, in the lab of Dr. Gregory Mark, I was involved in experiments where microinjections of cholinergic drugs into the Nucleus Accumbens Shell augmented the operant self-administration of cocaine, and in the lab of Dr. Deborah Finn, with the collaboration of Dr. Tamara Phillips, I was involved in experiments where the neurosteroid, allogregnanallone, a potent allosteric modulator of the GABAA receptor, was microinjected into the posterior ventral tegmental area, and potentiated the effect of ethanol to stimulate locomotor activity. For my dissertation, under the mentorship of Dr. Robert Hitzemann and Dr. Deborah Finn, I produced lesions in specific brain areas to elucidate the neuroanatomy that underlies ethanol consumption and ethanol vapor-induced increases in ethanol consumption.  Today, I use the stereotaxic skills that I developed at OHSU to produce both chemically and genetically-induced model of epilepsy in rats and mice.  My knowledge in studying behavior obtained from the program provided me with the background to analyze the anxiety and depressive-like behaviors that occur in the epilepsy models, allowing me to study animal models of the comorbidity that occurs between epilepsy and anxiety and depression.              

My OHSU Experience

The Behavioral Neuroscience program at OHSU is an excellent program.  The professors work well together and most share a common interest in drug abuse, mainly alcohol abuse (home of the Portland Alcohol Research Center), although other areas of behavioral research are also studied.  By attending the weekly graduate student seminars, I learned about many different animal behaviors.  My specific interest was in those that model psychiatric disorders, such as alcoholism, anxiety, and depression.  The faculty, post-doctoral fellows, and graduate students helped me to objectively analyze these animal behaviors, allowing me to determine strengths and weaknesses of each of the animal models.

My Portland Experience

Portland is a very fun city to live in.  It has a lot of culture, a variety of ethnic foods, a diversity of different types of music, and friendly, progressively-thinking people.  Portland is a very green city, and has some excellent farmers markets. It is very close to many beautiful mountains and rivers.  It is also very affordable, even for a graduate student.  The coffee is excellent, the public transportation is very efficient and effective, and the city is well designed for safe and enjoyable bicycling.  Overall, Portland is a very pleasant place to live.    

Publications  

R Dhaher, DA Finn, DL Oberbeck, N Yoneyama, CC Snelling, W Wu, RJ Hitzemann. Electrolytic Lesions of the Medial Nucleus Accumbens Shell Selectively Decrease Ethanol Consumption Without Altering Preference in a Limited Access Procedure in C57BL/6J Mice Pharmacology, Biochemistry, and Behavior 2009 92:335-342

R Dhaher, DA Finn, C Snelling, R Hitzemann, Lesions of the Extended Amygdala in C57BL/6J Mice Do Not Block the Intermittent Ethanol Vapor-Induced Increase in Ethanol Consumption.  Alcoholism: Clinical and Experimental Research 2008 32:197-208.  

R Dhaher, KK McConnell, ZA Rodd, WJ. McBride, RL Bell. Daily Patterns of Ethanol Drinking in Adolescent and Adult, Male and Female, High Alcohol Drinking (HAD) Replicate Lines of Rats.  Pharmacol Biochem Behav 2012 102:540-548

T Eid, K Behar, R Dhaher, AV Bumanglag, TW Lee. Roles of Glutamine Synthetase Inhibition in Epilepsy.  Neurochem Res. 2012:  April 10

R Dhaher, JE Toalston, SR Hauser, RL Bell, DL McKinzie, WJ McBride ZA Rodd. Effects of Naltrexone and LY255582 on Ethanol Maintenance, Seeking and Relapse Responding by Alcohol-Preferring (P) Rats. Alcohol 2012 46:17-27.

SR Hauser, B Getachew, SM Oster, R Dhaher, ZM Ding, RL Bell, WJ McBride, ZA Rodd. Nicotine Modulates Alcohol-Seeking and Relapse by Alcohol-Preferring (P) rats in a Time-Dependent Manner. Alcohol Clin Exp Res. 2012 36:43-54.

B Getachew, SR Hauser, R Dhaher, SN Katner, RL Bell, SM Oster, WJ McBride, ZA Rodd. CB1 Receptors Regulate Alcohol-Seeking Behavior and Alcohol Self-Administration of Alcohol-Preferring (P) Rats. Pharmacol Biochem Behav. 2011 97:669-75.

R Dhaher, SR. Hauser, B Getachew, RL. Bell, WJ. McBride, DL. McKinzie, ZA. Rodd  The Orexin-1 Receptor Antagonist SB-334867 Reduces Alcohol Relapse Drinking, but not Alcohol-Seeking, in Alcohol-Preferring (P) Rats  Journal of Addiction Medicine 2010 4:153-9.  

Page last updated: August 27, 2012