TY - JOUR
T1 - Stimulation of endorphin neurotransmission in the nucleus accumbens by ethanol, cocaine, and amphetamine.
AU - Olive, M. F.
AU - Koenig, H. N.
AU - Nannini, M. A.
AU - Hodge, C. W.
PY - 2001/12/1
Y1 - 2001/12/1
N2 - Numerous studies have demonstrated that drugs of abuse activate the mesolimbic dopamine reward pathway, and it is widely held that this activation contributes to the motivational and positive reinforcing properties of these substances. However, there is evidence that endogenous opioid systems within this brain reward circuit also play a role in drug reinforcement and drug-seeking behavior. Using microdialysis in freely moving rats, we sought to determine whether various drugs of abuse (i.e., ethanol, cocaine, d-amphetamine, and nicotine) would increase neurotransmission of endogenous opioid peptides (i.e., endorphins) in the nucleus accumbens. Drugs were administered intraperitoneally twice at 3 h intervals, and the endorphin content of microdialysates was analyzed by a solid-phase radioimmunoassay. Acute administration of ethanol, cocaine, and d-amphetamine transiently elevated extracellular levels of endorphins in the nucleus accumbens, whereas nicotine and saline were without effect. We hypothesize that this drug-induced release of endorphins may contribute to the positive reinforcing and motivating properties of ethanol and psychostimulants.
AB - Numerous studies have demonstrated that drugs of abuse activate the mesolimbic dopamine reward pathway, and it is widely held that this activation contributes to the motivational and positive reinforcing properties of these substances. However, there is evidence that endogenous opioid systems within this brain reward circuit also play a role in drug reinforcement and drug-seeking behavior. Using microdialysis in freely moving rats, we sought to determine whether various drugs of abuse (i.e., ethanol, cocaine, d-amphetamine, and nicotine) would increase neurotransmission of endogenous opioid peptides (i.e., endorphins) in the nucleus accumbens. Drugs were administered intraperitoneally twice at 3 h intervals, and the endorphin content of microdialysates was analyzed by a solid-phase radioimmunoassay. Acute administration of ethanol, cocaine, and d-amphetamine transiently elevated extracellular levels of endorphins in the nucleus accumbens, whereas nicotine and saline were without effect. We hypothesize that this drug-induced release of endorphins may contribute to the positive reinforcing and motivating properties of ethanol and psychostimulants.
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U2 - 10.1523/jneurosci.21-23-j0002.2001
DO - 10.1523/jneurosci.21-23-j0002.2001
M3 - Article
C2 - 11717387
AN - SCOPUS:0035654631
SN - 0270-6474
VL - 21
SP - RC184
JO - The Journal of neuroscience : the official journal of the Society for Neuroscience
JF - The Journal of neuroscience : the official journal of the Society for Neuroscience
IS - 23
ER -