Modulation of pre- and postsynaptic dopamine D2 receptor function by the selective kappa-opioid receptor agonist U69593

Effects of acute and repeated administration of salvinorin A on dopamine function in the rat dorsal striatum

“…These results are consistent with a previous study showing that repeated administration of U-69593 does not affect basal DA ext or DA uptake in the DSTR (Acri et al 2001). However, the findings in the DSTR differ from those showing that repeated administration of U-69593 decreases DA uptake but does not affect extracellular DA levels in the NAC (Thompson et al 2000).…”

“…Repeated U-69593 pretreatment attenuated the decrease in striatal DA dialysate levels produced by acute administration of the D2 receptor agonist quinpirole and reduced the locomotor stimulant effects of quinpirole (Acri et al 2001). Additionally, in the study where repeated administration of U-69593 significantly increased K + -evoked DA levels, quinpirole perfusion decreased basal and K + -evoked DA levels in control rats but not in rats pretreated with U-69593 (Fuentealba et al 2006).…”

Effects of acute and repeated administration of salvinorin A on dopamine function in the rat dorsal striatum

“…These results are consistent with a previous study showing that repeated administration of U-69593 does not affect basal DA ext or DA uptake in the DSTR (Acri et al 2001). However, the findings in the DSTR differ from those showing that repeated administration of U-69593 decreases DA uptake but does not affect extracellular DA levels in the NAC (Thompson et al 2000).…”

“…Repeated U-69593 pretreatment attenuated the decrease in striatal DA dialysate levels produced by acute administration of the D2 receptor agonist quinpirole and reduced the locomotor stimulant effects of quinpirole (Acri et al 2001). Additionally, in the study where repeated administration of U-69593 significantly increased K + -evoked DA levels, quinpirole perfusion decreased basal and K + -evoked DA levels in control rats but not in rats pretreated with U-69593 (Fuentealba et al 2006).…”

Kappa-Opioid Agonist U69593 Potentiates Locomotor Sensitization to the D2/D3 Agonist Quinpirole: Pre- and Postsynaptic Mechanisms

“…At first glance, there may seem a contradiction between the facilitating effects of kappa agonist treatment on sensitization to QNP observed in the present study and the reports in the literature showing that kappa agonists attenuate the response to QNP (Acri et al, 2001;Izenwasser et al, 1998), as well as sensitization to cocaine (Collins et al, 2001a, b;Shippenberg et al, 2001). However, there is a crucial difference in the timing of kappa agonist injections between our study and those reports: In the present study, the kappa agonist was always coadministered together with QNP.…”

Effects of the kappa opioid agonist U50,488 and the kappa opioid antagonist nor-binaltorphimine on choice between cocaine and food in rhesus monkeys

“…Two animals were also studied for up to 10 days after termination of U50,488 treatment, and no further changes in cocaine choice or response rates were observed (data not shown). This characterization of cocaine selfadministration after U50,488 treatment in rhesus monkeys bears a superficial resemblance to recent studies that examined mesolimbic D2 dopamine receptor density and function after daily treatment for three consecutive days with the kappa agonist U69,593 in rats (Acri et al 2001;Izenwasser et al 1998). In those studies, D2 receptor density was decreased 2 days after treatment, and the neurochemical and locomotor activating effects of the D2 agonist quinpirole were also diminished.…”

Effects of acute and repeated administration of salvinorin A on dopamine function in the rat dorsal striatum

“…These results are consistent with a previous study showing that repeated administration of U-69593 does not affect basal DA ext or DA uptake in the DSTR (Acri et al 2001). However, the findings in the DSTR differ from those showing that repeated administration of U-69593 decreases DA uptake but does not affect extracellular DA levels in the NAC (Thompson et al 2000).…”

“…Repeated U-69593 pretreatment attenuated the decrease in striatal DA dialysate levels produced by acute administration of the D2 receptor agonist quinpirole and reduced the locomotor stimulant effects of quinpirole (Acri et al 2001). Additionally, in the study where repeated administration of U-69593 significantly increased K + -evoked DA levels, quinpirole perfusion decreased basal and K + -evoked DA levels in control rats but not in rats pretreated with U-69593 (Fuentealba et al 2006).…”

Kappa-Opioid Agonist U69593 Potentiates Locomotor Sensitization to the D2/D3 Agonist Quinpirole: Pre- and Postsynaptic Mechanisms

“…At first glance, there may seem a contradiction between the facilitating effects of kappa agonist treatment on sensitization to QNP observed in the present study and the reports in the literature showing that kappa agonists attenuate the response to QNP (Acri et al, 2001;Izenwasser et al, 1998), as well as sensitization to cocaine (Collins et al, 2001a, b;Shippenberg et al, 2001). However, there is a crucial difference in the timing of kappa agonist injections between our study and those reports: In the present study, the kappa agonist was always coadministered together with QNP.…”

Effects of the kappa opioid agonist U50,488 and the kappa opioid antagonist nor-binaltorphimine on choice between cocaine and food in rhesus monkeys

“…Two animals were also studied for up to 10 days after termination of U50,488 treatment, and no further changes in cocaine choice or response rates were observed (data not shown). This characterization of cocaine selfadministration after U50,488 treatment in rhesus monkeys bears a superficial resemblance to recent studies that examined mesolimbic D2 dopamine receptor density and function after daily treatment for three consecutive days with the kappa agonist U69,593 in rats (Acri et al 2001;Izenwasser et al 1998). In those studies, D2 receptor density was decreased 2 days after treatment, and the neurochemical and locomotor activating effects of the D2 agonist quinpirole were also diminished.…”

Effects of acute and repeated administration of salvinorin A on dopamine function in the rat dorsal striatum

“…These results are consistent with a previous study showing that repeated administration of U-69593 does not affect basal DA ext or DA uptake in the DSTR (Acri et al 2001). However, the findings in the DSTR differ from those showing that repeated administration of U-69593 decreases DA uptake but does not affect extracellular DA levels in the NAC (Thompson et al 2000).…”

“…Repeated U-69593 pretreatment attenuated the decrease in striatal DA dialysate levels produced by acute administration of the D2 receptor agonist quinpirole and reduced the locomotor stimulant effects of quinpirole (Acri et al 2001). Additionally, in the study where repeated administration of U-69593 significantly increased K + -evoked DA levels, quinpirole perfusion decreased basal and K + -evoked DA levels in control rats but not in rats pretreated with U-69593 (Fuentealba et al 2006).…”

Kappa-Opioid Agonist U69593 Potentiates Locomotor Sensitization to the D2/D3 Agonist Quinpirole: Pre- and Postsynaptic Mechanisms

“…At first glance, there may seem a contradiction between the facilitating effects of kappa agonist treatment on sensitization to QNP observed in the present study and the reports in the literature showing that kappa agonists attenuate the response to QNP (Acri et al, 2001;Izenwasser et al, 1998), as well as sensitization to cocaine (Collins et al, 2001a, b;Shippenberg et al, 2001). However, there is a crucial difference in the timing of kappa agonist injections between our study and those reports: In the present study, the kappa agonist was always coadministered together with QNP.…”

Effects of the kappa opioid agonist U50,488 and the kappa opioid antagonist nor-binaltorphimine on choice between cocaine and food in rhesus monkeys

“…Two animals were also studied for up to 10 days after termination of U50,488 treatment, and no further changes in cocaine choice or response rates were observed (data not shown). This characterization of cocaine selfadministration after U50,488 treatment in rhesus monkeys bears a superficial resemblance to recent studies that examined mesolimbic D2 dopamine receptor density and function after daily treatment for three consecutive days with the kappa agonist U69,593 in rats (Acri et al 2001;Izenwasser et al 1998). In those studies, D2 receptor density was decreased 2 days after treatment, and the neurochemical and locomotor activating effects of the D2 agonist quinpirole were also diminished.…”