We investigated opioid peptide actions on somatic calcium-dependent action potentials of dorsal root ganglion (DRG) neurons grown in primary dissociated cell culture. We report that leucine-enkephalin decreased the duration and amplitude of DRG somatic calcium-dependent action potentials. The opioid peptide action was dose-dependent over 20 nM to 5 microM and was antagonized by naloxone, consis...

Through incentive learning, the emotional experience of a reward in a relevant need state (e.g. hunger for food) sets the incentive value that guides the performance of actions that earn that reward when the need state is encountered again. Opiate withdrawal has been proposed as a need state in which, through experience, opiate value can be increased, resulting in escalated opiate self-administ...

AIMS To investigate the patterns of concurrent sexual partnerships among young opiate users and sexual transmissibility of human immunodeficiency virus (HIV) in concurrent sexual partnerships in drug-use and sexual networks. DESIGN Cross-sectional design. PARTICIPANTS A total of 426 young opiate users in Yunnan, China. SETTING Young opiate users recruited from their network ties. MEASUR...

Aims: Scotland was the first country to adopt take-home naloxone (THN) as a funded public health policy. We summarise the background and rigorous set-up for before/after monitoring to assess the impact on high-risk opiate-fatalities. Methods: Evidence-synthesis of prospectively monitored small-scale THN schemes led to a performance indicator for distribution of THN-kits relative to opiate-relat...

Previous pharmacological studies have implicated serotonergic brain systems in opiate withdrawal. To test the hypothesis that serotonin (5-HT) has a critical role in the development of opiate withdrawal, we have employed a near-total brain 5-HT system lesion technique (90% depletion) using 5,7-dihydroxytryptamine combined with induction of opiate dependence by implantation of morphine pellets o...

The present study aims to explore whether an impairment in emotional facial expressions (EFE) decoding is specific to alcoholism compared with opiate dependence. An EFE decoding test consisting of 16 photographs of EFE portraying happiness, anger, sadness and disgust was administered to five different groups of 30 subjects each: recently detoxified alcoholics (RA); opiate addicts under methadon...

Repeated exposure to opiates produces analgesic tolerance, which limits their clinical usefulness. Whole-cell voltage-clamped lamina I cells in spinal slices from opiate-tolerant neonatal rats show an increase in miniature, spontaneous, and primary afferent-evoked EPSCs when compared with lamina I cells from opiate-naive rat spinal slices. This increased excitation can be blocked by the NMDA re...

conclusions low onset age of smoking cigarettes, high novelty seeking and low cooperativeness in opiate dependents are among the important personality traits in future use of drugs that can predict the subsequent onset of using opiate drugs. results opiate addicts had higher scores in novelty seeking dimension and lower scores in cooperativeness compared to nicotine addicts. the onset age of sm...

The study of neuronal adaptations induced by opiate drugs is particularly relevant today given their widespread prescription and nonprescription use. Although much is known about the acute actions of such drugs on the nervous system, a great deal of work remains to fully understand their chronic effects. Here, we focus on longer-lasting adaptations that occur in two catecholaminergic brain regi...