Toadfish

People

Lead PI

Danielle McDonald
M. Danielle McDonald, Ph.D.
Assistant Professor

“Currently looking for an enthusiastic and hardworking Ph.D. student”


Undergraduate Students

 
Maria Cartolano
2011–present
 
Joshua Lonthair
2012
 
Sara Marin
2011–present
 
Haley Nicholson
2012
 
Jennifer Panlilio
2012
 
Abigail Wisnet
2012

Former Graduate Students

Lea Medeiros
Lea R. Medeiros
Ph.D.
June 2007—April 2012
Alex Frere
Alexander W. Frere
M.S.
June 2010—April 2012

Former Lab Members: Research Assistants

Michael Morando
Michael B. Morando
Fall 2006–August 2007
Alexander Gonzalez
Alexander Gonzalez
Summer 2008
Isabel Zuclich
Isabel Zuclich
August 2008–Spring 2009
Clare Owen
Clare Owen
Summer 2009

Former Lab Members: Undergraduate Students

Lara Polansky
Lara Yael Polansky
2006–2007
Alexander Gonzalez
Alexander Gonzalez
2009–2010
 
Kelly Kavanaugh
2009–2010
 
Courtney Alexander
2009–2010
 
Brittney Macdonald
2010–2011
 
Anthony Lange
2011–2012

Lea Medeiros
Research Statement

My current research investigates how the stress response, and in particular cortisol, plays a role in mediating changes in transcription, binding and functional responsiveness of the serotonin subtype 1A (5-HT1A) receptor in the Gulf toadfish, Opsanus beta. The 5-HT1A receptor plays an important role in maintaining the homeostatic balance between serotonin and cortisol by stimulating the release of cortisol from the interrenal cells when bound by serotonin. In mammals, there is a classical negative feedback loop whereby high levels of cortisol downregulate expression of the 5-HT1A receptor to decrease the release of cortisol in response to chronically elevated plasma cortisol. I am interested in seeing if this system exists in the Gulf toadfish, and also how the changes effected by cortisol are mediated. My long term goal is to relate changes in circulating levels of cortisol, serotonin and the 5-HT1A receptor to changes in reproductive activity. Additionally, because antidepressants are known to affect the 5-HT1A receptor, I am interested in how antidepressants may be upsetting the natural balance between the three (cortisol, serotonin and the 5-HT1A receptor) in a way that affects reproduction. As the Gulf toadfish exhibit very predictable and obvious reproductive behaviors I hope they will prove to be an excellent animal to study this complicated system

Alex Frere
Research Statement

Toadfish tolerate stress well. As we methodically stress our fish in the lab, their biochemistry begins to alter. Their cortisol levels elevate and they change their nitrogenous waste from strictly ammonia to a combination of mostly urea with ammonia as well. This predator avoidance technique utilizes both the glucocorticoid pathway and the serotonin receptor, 5-HT-2A. My work in our lab revolves around determining exactly what role the 5-HT-2A receptor plays in this complex loop, and how stress affects its ability to perform this role. Currently, I am characterizing the pharmacology of the 5-HT-2A receptor so that later we can establish which stressors alter its baseline mRNA expression, binding kinetics and function and how. Varying the amount of stress and the type of stressor should also provide interesting results. Toadfish elevate their stress in response to a variety of stimuli including sound and alpha-beta dominance-like interactions. Using these as novel stressors will hopefully provide us with more information on how 5-HT-2A functions, as little is known about its action other than that it is heavily involved in many serious human conditions such as anxiety, depression, anorexia, and a form of violent suicide.

 

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