Publications by authors named "Eden V Harder"
Engagement of astrocytes within the brain's reward circuitry has been apparent for approximately 30 years, when noncontingent drug administration was observed to lead to cytological markers of reactive astrocytes. Since that time, advanced approaches in rodent behavior and astrocyte monitoring have revealed complex interactions between astrocytes with drug type, animal sex, brain region, and dose and duration of drug administration. A number of studies now collectively reveal that rodent drug self-administration followed by prolonged abstinence results in decreased features of structure and synaptic colocalization of astrocytes.
View Article and Find Full Text PDFIn recent years, astrocytes have been increasingly implicated in cellular mechanisms of substance use disorders (SUD). Astrocytes are structurally altered following exposure to drugs of abuse; specifically, astrocytes within the nucleus accumbens (NAc) exhibit significantly decreased surface area, volume, and synaptic colocalization after operant self-administration of cocaine and extinction or protracted abstinence (45 days). However, the mechanisms that elicit these morphological modifications are unknown.
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- Astrocytes play a crucial role in regulating glutamatergic signaling, and their shape can change based on environmental factors, but the impact of early life experiences on their morphology is still not well understood.
- In a study using a postnatal resource scarcity model in rats, it was found that limited bedding and nesting (LBN) can enhance maternal behaviors and lead to greater resilience against addiction behaviors in adulthood, which involves changes in the medial orbitofrontal and medial prefrontal cortices.
- The research indicated that LBN exposure results in increased size of astrocytes in these brain regions for both male and female rats, with sex-specific transcriptional changes impacting glutamatergic signaling, suggesting
Article Synopsis
- Astrocytes, which are star-shaped brain cells, play a crucial role in regulating glutamatergic signaling and their structure can change based on environmental conditions.
- A study used a method called limited bedding and nesting (LBN) in rats, finding that early life resource scarcity led to increased astrocyte size in specific brain areas related to decision-making and addiction in adulthood.
- The research identified sex-specific gene expression changes related to glutamatergic signaling that could explain how LBN affects astrocyte morphology, suggesting that early resource deprivation can have significant long-term effects on brain function.
Accumulating evidence indicates significant consequences for astrocytes associated with drug abuse. For example, reductions in structural features and synaptic colocalization of male rat nucleus accumbens (NAc) astrocytes are observed following short-access (ShA; 2 h/d) self-administration and extinction from cocaine, methamphetamine, and heroin. However, it is unknown whether these observations extend to other rodent models of drug abuse, how enduring these effects may be, and whether similar effects are observed in female rats.
View Article and Find Full Text PDFΔ-tetrahydrocannabinol (THC) is the intoxicating constituent of cannabis and is responsible for the drug's reinforcing effects. Retrospective human studies suggest that cannabis use during adolescence is linked to long-term negative psychological outcomes, but in such studies it is difficult to distinguish the effects of THC from those of coexisting factors. Therefore, translationally relevant animal models are required to properly investigate THC effects in adolescents.
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