The dopamine D1 receptor agonist and D2 receptor antagonist LEK-8829 attenuates reinstatement of cocaine-seeking in rats

Involvement of the dopamine receptors in the basolateral amygdala (BLA) in the effects of histamine on anxiety-like behaviors of the elevated plus maze in male Wistar rats was investigated. The results showed that bilateral intra-BLA injections of histamine (2.5, 5 and 7.5 µg/rat) induced an anxiogenic-like effect, revealed by decreases in percentage of open arm time (%OAT) and open arm entries (%OAE). Intra-BLA administration of dopamine D1 receptor agonist, SKF38393 (0.25 µg/rat), and dopamine D2 receptor agonist, quinpirole (0.03 and 0.05 µg/rat), decreased %OAT but not %OAE. Conversely, intra-BLA administration of dopamine D1 receptor antagonist, SCH23390 (0.5 and 1 µg/rat), and dopamine D2 receptor antagonist, sulpiride (0.3 and 0.5 µg/rat), increased %OAT and %OAE, suggesting an anxiolytic-like effect for both drugs. Interestingly, co-administration of a silent dose of SCH23390 or sulpiride prevented anxiogenic-like effects of SKF38393 and quinpirole, respectively. Conjoint administration of a sub-effective dose of SKF38393 (0.125 µg/rat) or quinpirole (0.01 µg/rat) along with lower doses of histamine (1 and 2.5 µg/rat) induced anxiolytic-like effects. On the other hand, intra-BLA pretreatment with a silent dose of SCH23390 (0.25 µg/rat) or sulpiride (0.1 µg/rat) prevented the anxiogenic-like effect of higher doses of histamine (5 and 7.5 µg/rat). No significant change was observed in total closed arm entries, as an index for motor activity of the animals. It can be concluded that the dopamine D1 and D2 receptors in the BLA may be involved in the anxiogenic-like effects induced by histamine.

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L-Stepholidine, a naturally occurring dopamine D1 receptor agonist and D2 receptor antagonist, attenuates heroin self-administration and cue-induced reinstatement in rats

Neuroreport ◽

10.1097/wnr.0000000000000012 ◽

2013 ◽

pp. 1 ◽

Cited By ~ 2

Author(s):

Kai Yue ◽

Baomiao Ma ◽

Lin Chen ◽

Xiang Tian ◽

Qin Ru ◽

...

Keyword(s):

Receptor Antagonist ◽

Receptor Agonist ◽

D2 Receptor ◽

Dopamine D1 Receptor ◽

D1 Receptor ◽

Self Administration ◽

Naturally Occurring

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Dopamine D1 Receptor Agonist and D2 Receptor Antagonist Effects of the Natural Product (−)–Stepholidine: Molecular Modeling and Dynamics Simulations

Biophysical Journal ◽

10.1529/biophysj.106.088500 ◽

2007 ◽

Vol 93 (5) ◽

pp. 1431-1441 ◽

Cited By ~ 32

Author(s):

Wei Fu ◽

Jianhua Shen ◽

Xiaomin Luo ◽

Weiliang Zhu ◽

Jiagao Cheng ◽

...

Keyword(s):

Molecular Modeling ◽

Receptor Antagonist ◽

Natural Product ◽

Receptor Agonist ◽

D2 Receptor ◽

Dopamine D1 Receptor ◽

D1 Receptor ◽

Dynamics Simulations

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Characterization of dopamine receptors mediating inhibition of excitatory synaptic transmission in the rat hippocampal slice

Journal of Neurophysiology ◽

10.1152/jn.1996.76.3.1887 ◽

1996 ◽

Vol 76 (3) ◽

pp. 1887-1895 ◽

Cited By ~ 54

Author(s):

K. S. Hsu

Keyword(s):

Synaptic Transmission ◽

Receptor Antagonist ◽

Receptor Agonist ◽

Hippocampal Slices ◽

D2 Receptor ◽

D1 Receptor ◽

Excitatory Synaptic Transmission ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Ca1 Neurons

1. The effect of dopamine (DA) on the excitatory synaptic transmission was studied in the CA1 neurons of rat hippocampal slices using intracellular recording technique. 2. Depolarizing excitatory postsynaptic potentials (EPSPs) were evoked by stimulation of the Schaffer collateral-commissural pathway. Superfusion of DA (0.03-1 microM) reversibly decreased the EPSP in a concentration-dependent manner and with an estimated IC50 of 0.3 microM. The sensitivity of postsynaptic neurons to the glutamate-receptor agonists, alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid or N-methyl-D-aspartate was unchanged by DA (0.3 microM) pretreatment. In addition, DA (0.3 microM) increased the magnitude of paired-pulse facilitation, a phenomenon attributed to an increase in the amount of transmitter released in response to the second stimulus. 3. The reduction of DA (0.3 microM) on the EPSP was antagonized by sulpiride (1-10 nM), a selective D2-receptor antagonist. However, D1-receptor antagonist, SKF-83566 (1-10 microM), did not significantly affect the reduction of DA (0.3 microM) on the EPSP. 4. (+/-)-2-(N-Phenylethyl-N-propyl)amino-5-hydroxytetralin (1 microM), an agonist of D2 receptor, mimicked the inhibitory effect of DA on the EPSP. However, neither the D1-receptor agonist SKF-38393 (1 microM) nor the D3-receptor agonist (PD-128,907 (1 microM) affected the EPSP. 5. Incubation of hippocampal slices with pertussis toxin (PTX, 5 micrograms/ml) for 12 h prevented the reduction of EPSP induced by DA (0.3 microM). 6. Rp-adenosine-3',5'-cyclic monophosphothioate (25 microM), a potent inhibitor of protein kinase A (PKA), alone decreased the amplitude of EPSP below baseline values and prevented the subsequent reduction by DA (0.3 microM). 7. These results indicate that DA at a low concentration (< or = 0.3 microM) reduces the excitatory response of hippocampal CA1 neurons after synaptic stimulation via the activation of presynaptic D2 receptors. The presynaptic action of DA is mediated by a PTX-sensitive Gi-proteins-coupled to PKA pathway.

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