Psychopharmacology
-
The use and misuse of prescription opiates in adolescent populations, and in particular, adolescent female populations, has increased dramatically in the past two decades. Given the significant role that opioids play in neuroendocrine function, exposure to opiates during this critical developmental period could have significant consequences for the female, as well as her offspring. ⋯ These results suggest significant modifications in response to repeated D2R activation in the progeny of females exposed to opiates during adolescence. Given the significant role that the D2R plays in psychopathology, adolescent opiate exposure could shift the vulnerability of future offspring to psychological disorders, including addiction. Moreover, that effects are also observed in the F2 generation suggests that adolescent opiate exposure can trigger transgenerational epigenetic modifications impacting systems critical for motivated behavior.
-
Isolation rearing in rodents causes not only abnormal behaviors which resemble the clinical symptoms of schizophrenia but also hypoalgesia in thermal nociception models. However, the mechanism of the hypoalgesia is not known. ⋯ These findings suggest that isolation rearing causes hypoalgesia in mouse models of acute pain and imply that the spinal 5-HT1A receptor activation probably through descending serotonergic inhibitory pathway is involved in isolation rearing-induced hypoalgesia.
-
Hypericum perforatum, popularly called St. John's wort (SJW), is a medicinal plant mainly used as antidepressant with a favorable safety profile than standard antidepressants. Some studies have also documented other SJW bioactivities, including pain modulation. ⋯ SJW reversed NO-induced nociceptive hypersensitivity through the blockade of a supraspinal signaling pathway involving a PKC-dependent CREB, STAT1 and NF-κB activation due to presence of hypericin. These data indicate SJW/hypericin as a therapeutic perspective for pain treatment.
-
Comparative Study
Common influences of non-competitive NMDA receptor antagonists on the consolidation and reconsolidation of cocaine-cue memory.
Environmental stimuli or contexts previously associated with rewarding drugs contribute importantly to relapse among addicts, and research has focused on neurobiological processes maintaining those memories. Much research shows contributions of cell surface receptors and intracellular signaling pathways in maintaining associations between rewarding drugs (e.g., cocaine) and concurrent cues/contexts; these memories can be degraded at the time of their retrieval through reconsolidation interference. Much less studied is the consolidation of drug-cue memories during their acquisition. ⋯ Using two distinct NMDA receptor antagonists in a common setting, these findings demonstrate that NMDA receptor-dependent processes contribute both to the consolidation and reconsolidation of cocaine-cue memories, and they point to the potential utility of treatments that interfere with drug-cue memory reconsolidation.
-
Impulsive behavior is categorically differentiated between impulsive action, the inability to withhold from acting out a response, and impulsive choice, the greater preference for an immediate and smaller reward over a delayed but more advantageous reward. While the effects of N-methyl-D-aspartic acid (NMDA) receptor antagonists on impulsive action have been extensively characterized, there are very few and conflicting reports on the effects of this class of drugs on impulsive choice. ⋯ NMDA receptor uncompetitive, but not competitive, antagonists significantly increased impulsive choice, preferentially in low-impulsive rats. These findings demonstrate that the effects of NMDA receptor blockade on impulsive choice are not generalizable and depend on the specific mechanism of action of the antagonist used.