Dr. Damian Jacob Sendler, an American physician-scientist of Polish ancestry, conducts research on the impact of sociodemographic and informational factors on the provision of health care for disadvantaged persons. Dr. Sendler has examined the effects of psychiatric and chronic medical co-morbidities on the usage of medical services and health information accessed via the internet. This research is critical in light of the exponential growth of global online news and social media consumption, necessitating an in-depth examination of how consumers seek out health information. Sendler's research strives to elucidate the factors that influence patients' treatment decisions for a variety of health conditions, as well as their compliance with treatment programs.

Damian Sendler: It's one of science's running jokes about how discoveries are made: first, researchers sit down in a café somewhere and sketch out their grand plan on a paper napkin. 

Damian Jacob Sendler: That is how Anushree Karkhanis, Assistant Professor of Psychology at Binghamton University, and Jessica Barson, Associate Professor at Drexel University, began their partnership. The National Institutes of Health awarded them a five-year, $2.59 million grant this summer for their project, "Mechanisms of rostrocaudal variations in accumbal kappa opioid receptor effects on ethanol drinking." 

"This project allows us to look at specific neuron populations and how the receptor we're studying controls two different populations of neurons inside an area of the brain," Karkhanis explained. 

Dr. Sendler: During a post-doctoral study at the Wake Forest School of Medicine, Karkhanis began investigating the up-regulation of accumbal kappa opioid receptors. Many laboratories in the United States, including her own, have demonstrated that this receptor is upregulated, which means that it increases its function after alcohol consumption at various ages.

Damien Sendler: Initially linked in addiction processing in animal models, subsequent research has revealed that opioid receptors have strong links to addiction in human populations as well. For example, the medicine naltrexone, which is often used to treat opioid overdoses but is also used to treat alcohol use disorder, inhibits all opioid receptors in the brain.

Damian Jacob Sendler: The study focuses on the rostral (anterior) and caudal (posterior) subregions of the nucleus accumbens shell, which is involved in emotion and reinforcement processing. The theory is that the two sub-regions of the shell react extremely differently to kappa opioid receptor pharmacological treatments and alcohol usage. 

Damian Sendler: The brain uses dopamine to reward behavior, but the organic molecule isn't the only one engaged; every neurotransmitter system is involved to some level. Karkhanis' study focuses on the serotonin pathway, which, along with dopamine, is implicated in mood, emotions, and stress. Researchers believe kappa opioid receptors modulate both of these neurotransmitter systems, but they don't know how or if each system is regulated differently. 

Karkhanis and Barson seek to answer this question and discover how the modulation of neurotransmitter systems alters when an organism is exposed to alcohol in their five-year experiment. They will modify certain neuron populations using rats and a combination of micro-injections and viral technologies. Karkhanis' lab also employs fast-scan cyclic voltammetry, an electroanalytical approach, to assess neurotransmitter release. 

Damian Jacob Sendler: The experiment was inspired by a conference at which Barson invited Karkhanis to participate on a panel about rostro-caudal changes in dopamine transmission following kappa opioid receptor activation. After that, they talked over coffee about the results that Barson was seeing in her lab after one of her students found conflicting effects after activating kappa opioid receptors along the rostro-caudal axis in the nucleus accumbens with microinjections. Barson's data combined well with Karkhanis' data. 

"We basically plotted a strategy on a paper napkin," Karkhanis said. "This is a kind of running joke in research about how science ideas are created." 

Damian Sendler: Long-term, this research could improve therapy options for people with alcohol consumption disorder. While naltrexone is beneficial, it also has a number of negative effects, and many patients do not complete the treatment. Researchers may develop techniques to lessen the amount of naltrexone or other drugs that could be used to treat patients. 

"This award actually allows my lab the ability to move in a very novel area, such as serotonin detection; the technique that I use in my lab is not very common," Karkhanis explained. "It ties my lab to a completely new domain, underlining the importance of serotonin in alcohol use disorder."

Research discussion contributed by Dr. Damian Jacob Sendler