Skip to main content

Sex differences in drug abuse behavior

By
Venniro (2018)
When I was reading Experiment 1, I noticed that the authors only mentioned males for the methamphetamine experiments and mentioned both males and females for the heroin experiments which was interesting. It was positive that both sexes were being used in this experiment but not clear why only for the heroin experiment. I referred to the methods and there were 318 male rats and only 39 female rats used in this study, about 11%. Why wouldn’t the researchers use a ratio closer to 50/50 of male and female rats? I don’t know much about laboratory rat breeding but I would assume it’s not due to a shortage of females since most studies use only males. Why were all the females in the heroin group and none in the methamphetamine group? It says rats were randomly assigned to drug user and drug naive groups but it doesn’t say that they were randomly assigned to drug type groups. And if they were randomly assigned, it’s unlikely that all of the females were assigned to the heroin group. So their results show that sex does not have an effect on preference of social interaction or heroin but sex may have an effect on preference of social interaction or methamphetamine that has not been explored.
In experiment 3, the results show that the medium addiction group had higher resistance to punishment of social reward. I wonder where there was a bell curve here. It would make sense for the high addiction group to give up the social reward faster if there was punishment because their addiction is stronger so a social reward may not be that much more enticing than the drug to begin with. However, I’m not sure why the low addiction group would have low resistance to the social reward punishment as well.
An interesting next step for this research could be to see what kinds of stresses can undo the protection from incubation of craving brought on by abstinence. Humans after drug addiction treatment may turn to drugs again in order to deal with stressors so it would be interesting to see how strong this protection is against chronic mild stress, acute traumatic stress, etc.

de Guglielmo (2019)
I noticed this paper discussed rats being dependent on alcohol rather than saying they are addicted to alcohol. Any mentions of addiction in this paper used the term addiction-like. It reminds me of some of the papers we read previously that used phrases like “depressive-like phenotypes” or “anxiety-like behaviors” that used those terms since they can’t accurately call a rodent depressed. I wonder to what extent does that apply to addiction. Two out of the three components of addiction this paper lists are observable behaviors. Is it possible to diagnose rodents with addiction or is it not, such as with depression?

Comments

Post a Comment

Popular posts from this blog

Week 2- Dopamine Modulation of Depressive-like Behaviors

By
The Chaudhury et al paper explored the neural circuit mechanisms involved in the dopamine modulation of certain symptoms of depression. In this study, the researchers looked at social interaction and sucrose preference as part of their social-defeat paradigm, which has been shown in the past to be indicative of depressive-like behaviors. Although I initially did not completely see the connection between the social-defeat stress model of depression and the tonic vs phasic firing of dopamine neurons, it seemed that susceptibility and resilience to stress played a role in the functional/behavioral effects of dopamine firing. It was interesting to see how chronic mild stress with phasic firing of VTA dopamine neurons converted even resilient mice into susceptible mice.  The Tye et al paper similarly looked at the dopamine modulation of depressive-like behaviors, focusing on motivation with the forced swim tests and open field tests, followed by measurement of anhedonia by quantifyi...
Post a Comment
Read more

Sial & Allsop

By
Sial et al. derived a novel approach for studying what they deem vicarious defeat stress (VSDS) as a model for MDD, PTSD, and other mood-related disorders as an alternative to the classical CSDS paradigm. Using adult male mice, they demonstrate that their model induces a robust and measurable social avoidant phenotype as well as other stress and anxiety related behavioral outputs. Their subsequent rescue study with chronic fluoxetine treatment shows reversal of the behavioral phenotypes and emphasizes the predictive validity of the model. Allsop et al. found that BLA-projecting ACC neurons preferentially encode socially derived aversive cue information by encoding the demonstrator’s distress response during observational learning, hence enabling acquisition of negative valence of cue by BLA neurons and behavioral output. In order to test their hypothesis, Allsop et al. used an observational fear conditional paradigm to create association between a conditioned stimulu...
Post a Comment
Read more

Buffington and Reber

By
Buffington et al. explore a mechanism by which maternal obesity can induce neuronal and subsequent behavioral disorders. Using a model of high-fat diet (MHFD)-induced obesity, the authors showcase the strong connection between the brain and the gut, and its impact on behavior. The findings are provocative; by exposing these offspring to the microbiome of control offspring, there was evidence of a rescued observed behavioral phenotype. Furthermore, a phylogenetic profiling of the gut microbiome revealed a decrease in L. reuteri within MHFD offspring, and introduction of live L. reuteri into the drinking water shows successful rescue of the behavioral issues in the MHFD offspring. L. reuteri-induced expression of oxytocin within the paraventricular nuclei of the hypothalamus provides a potential mechanistic explanation for the behavioral changes. I thought this paper provided robust support for the hypothesized interaction between the gut biome and the developing CNS, with tremendous po...
Post a Comment
Read more