Bogdan Szukalski
Neurobiologiczne podstawy uzależnienia od narkotyków
2009-09-15
Neurobiological Bases of Drug Dependence. Addiction is a chronic complex and recurring disorder characterized by anomalous behaviors that are linked to permanent or long-lasting neurobiological alterations. The disorder of addiction involves the progression of acute drug use to the development of drug-seeking behavior. Elucidation of the roles of neurotransmitters and specific molecules in the development of drug dependence can come from preclinical animal models and from clinical data. Among animal models, behavioral sensitization, conditioned place preference, drug discrimination and drug self-administration have been widely used.The nucleus accumbens (NAc) is a critical element of the mesocorticolimbic system, a brain circuit implicated in reward and motivation. This basal forebrain structure receives dopamine (DA) input from the ventral tegmental area (VTA) and glutamate (GLU) input from regions including the prefrontal cortex (PFC) and hippocampus (HIP).
There is accumulating evidence indicating a central role for the previously unknown but ubiquitous endocannabinoid physiological control system (EPSC) in the regulation of the rewarding effects of abused substances. Endocannabinoids mediate retrograde signaling in neuronal tissues and are involved in the regulation of synaptic transmission to suppress neurotransmitter release by the presynaptic cannabinnoid receptors (CB-Rs). In this paper we have reviewed hypothetical mechanisms underlying the development of addiction.
Keywords: dopamine, drug addiction, reward system, relapse, endocannabinoids.