The dopamine D3 receptor antagonist VK4-116 reduced oxycodone self-administration in rats, as well as drug-seeking behaviors after oxycodone reinstatement following withdrawal. VK4-116 did not interfere with oxycodone’s pain-relieving effects
In animal studies, α2δ-1 and its interactions with NMDA receptors in the spinal cord triggered the pain sensitivity and analgesic tolerance that occurs with chronic morphine treatment. Blocking the α2δ-1–NMDA interaction reduced opioid-induced hyperalgesia and analgesic tolerance.
This study showed that rats will forgo heroin and methamphetamine in favor of spending time with another rat. It also highlights the importance of incorporating voluntary choice between drugs and social rewards in drug addiction research.
Exposing adolescent rats to THC disrupted normal maturation of a key set of neurons in a brain area that corresponds to the human prefrontal cortex. The disruptions produced structural differences that resemble patterns which have been observed in people with addiction and schizophrenia.
These findings add to research showing that nicotine and cannabis have interactive effects on brain structure and function. They also suggest that specialized treatment interventions may be appropriate for people who use both drugs.
People with cannabis dependence have changes in neural circuitry in brain regions related to reward processing, habit formation, and psychopathology. These changes in neural circuitry may provide a useful marker for tracking psychopathology associated with cannabis misuse.
This study demonstrated that cocaine increases expression of the protein E2F3a in the brain’s reward system. The changes in E2F3a levels in the nucleus accumbens are tied to addiction-related behaviors and to altered gene expression.