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Post 9: Animal models of addiction prevention and reversal

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Many papers we have studied this semester have focused on the induction of mental illness in mental illness as a means of understanding disease and potentially recognizing targets for treatment. While these efforts are very beneficial and make headway in the field, I was excited that Venniro et al. (2018) and de Guglielmo et al. (2019) focused directly on preventing and reversing models of mental illness—specifically addiction. While the papers used very different methods to do so, both identified neuronal ensembles in the central nucleus of the amygdala (CeA) as being important for aspects of addiction. These overlapping findings helped to confirm my understanding of the significance of the CeA in relation to addiction. As neurotransmitters were only briefly discussed in these papers and GABA and glutamate are known to have roles in addiction, I would be very interested in learning more about the roles of GABAergic and glutamatergic transmission in the CeA’s mediation of addictive behaviors. 

While the aforementioned findings about the CeA’s role in addiction, as well as many others in de Guglielmo, were strong and well-supported, I found it difficult to ignore the lack of clarity of their methods. The timelines for many of the procedures including operant self-administration of alcohol and saccharine, behavioral testing, and ethanol self-administration sessions during vapor exposure contained numerous gaps that would make this experiment difficult to replicate. Additionally, a number of small mistakes in the text in reference to figures added to the confusion I had in comprehending the methods. A final minor critique of the de Guglielmo paper is that its suggestions for future study, while important to consider, do not call upon previously discussed limitations of the paper, though they seem to be presented as such. I was somewhat surprised by these suggestions when I came to them, instead expecting recommendations about studying the role of neurotransmitters in the CRFCeA-BNST pathway or further investigation of the CRF-CRF1system.

Thinking more broadly, the findings of Venniro et al. increased my concern and curiosity about the effects of current mandated social distancing on individuals suffering from mental illnesses. While I have reflected on the negative effects that staying at home may have for those with depression, widespread uncertainty about the future may have for those with anxiety, and endless demands to wash hands may have on those with obsessive compulsive disorder, I have not as closely considered how social distancing may increase drug addiction. Learning about the protective factors of social interaction in rodent models of addiction significantly increased my awareness of how considerably individuals susceptible to addiction or relapse may be at this time. Venniro et al. recognize a powerful protective factor against drug addiction in rats that may have similar protective factors in humans, and in doing so they predict the increased potential for individuals at risk to turn to drugs during these unprecedented times. 

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