Abstract
To better understand the influence of κ-opioid agonists on the effects of cocaine, rats were treated with daily injections of the selective κ-opioid agonist U-69593 or bremazocine. In combination with 10mg/kg cocaine, both compounds, at a dose of 0.32 mg/kg, greatly diminished locomotor activity, and these effects were maintained over a period of 5 days. In addition, the response to a challenge injection of 10mg/kg cocaine several days after the end of κ-opioid agonist treatment with or without cocaine was markedly reduced. When naltrexone was given in combination with U-69593, it blocked the reduction in cocaine-induced locomotor activity after U-69593 treatment alone. However, a single injection of either κ-opioid agonist alone had no effect on cocaine-induced locomotion several days later (i.e. no long-term effects), suggesting that multiple injections of the κ-opioid agonist are needed to reduce the locomotor activating effects of cocaine other than acutely. In addition, treatment with the κ-opioid agonist U-69593 (0.32 mg/kg) over a 5-day period decreased dopamine transporter densities in the caudate putamen, and this was also blocked by co-administration of naltrexone.
| Original language | English |
|---|---|
| Pages (from-to) | 237-245 |
| Number of pages | 9 |
| Journal | Behavioural Pharmacology |
| Volume | 12 |
| Issue number | 4 |
| State | Published - Aug 20 2001 |
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Keywords
- κ-opioid
- Cocaine
- Dopamine transporter
- Locomotor activity
- Rat
- Sensitization
ASJC Scopus subject areas
- Pharmacology
- Neuroscience(all)
Cite this
Kappa opioid agonists alter dopamine markers and cocaine-stimulated locomotor activity. / Collins, S. L.; Gerdes, R. M.; Addario, C. D.; Izenwasser, Sari E.
In: Behavioural Pharmacology, Vol. 12, No. 4, 20.08.2001, p. 237-245.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Kappa opioid agonists alter dopamine markers and cocaine-stimulated locomotor activity
AU - Collins, S. L.
AU - Gerdes, R. M.
AU - Addario, C. D.
AU - Izenwasser, Sari E
PY - 2001/8/20
Y1 - 2001/8/20
N2 - To better understand the influence of κ-opioid agonists on the effects of cocaine, rats were treated with daily injections of the selective κ-opioid agonist U-69593 or bremazocine. In combination with 10mg/kg cocaine, both compounds, at a dose of 0.32 mg/kg, greatly diminished locomotor activity, and these effects were maintained over a period of 5 days. In addition, the response to a challenge injection of 10mg/kg cocaine several days after the end of κ-opioid agonist treatment with or without cocaine was markedly reduced. When naltrexone was given in combination with U-69593, it blocked the reduction in cocaine-induced locomotor activity after U-69593 treatment alone. However, a single injection of either κ-opioid agonist alone had no effect on cocaine-induced locomotion several days later (i.e. no long-term effects), suggesting that multiple injections of the κ-opioid agonist are needed to reduce the locomotor activating effects of cocaine other than acutely. In addition, treatment with the κ-opioid agonist U-69593 (0.32 mg/kg) over a 5-day period decreased dopamine transporter densities in the caudate putamen, and this was also blocked by co-administration of naltrexone.
AB - To better understand the influence of κ-opioid agonists on the effects of cocaine, rats were treated with daily injections of the selective κ-opioid agonist U-69593 or bremazocine. In combination with 10mg/kg cocaine, both compounds, at a dose of 0.32 mg/kg, greatly diminished locomotor activity, and these effects were maintained over a period of 5 days. In addition, the response to a challenge injection of 10mg/kg cocaine several days after the end of κ-opioid agonist treatment with or without cocaine was markedly reduced. When naltrexone was given in combination with U-69593, it blocked the reduction in cocaine-induced locomotor activity after U-69593 treatment alone. However, a single injection of either κ-opioid agonist alone had no effect on cocaine-induced locomotion several days later (i.e. no long-term effects), suggesting that multiple injections of the κ-opioid agonist are needed to reduce the locomotor activating effects of cocaine other than acutely. In addition, treatment with the κ-opioid agonist U-69593 (0.32 mg/kg) over a 5-day period decreased dopamine transporter densities in the caudate putamen, and this was also blocked by co-administration of naltrexone.
KW - κ-opioid
KW - Cocaine
KW - Dopamine transporter
KW - Locomotor activity
KW - Rat
KW - Sensitization
UR - http://www.scopus.com/inward/record.url?scp=0034897489&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034897489&partnerID=8YFLogxK
M3 - Article
C2 - 11548109
AN - SCOPUS:0034897489
VL - 12
SP - 237
EP - 245
JO - Behavioural Pharmacology
JF - Behavioural Pharmacology
SN - 0955-8810
IS - 4
ER -