Synergistic effects of D1 and D2 dopamine agonists on turning behaviour in rats

doi:10.1016/0006-8993(86)91178-9

Brain Research

Volume 384, Issue 2, 8 October 1986, Pages 387-390

https://doi.org/10.1016/0006-8993(86)91178-9 Get rights and content

Abstract

In rats with unilateral 6-hydroxydopamine lesions of the substantia nigra, a specific D₁ dopamine receptor agonist, SKF 38393A, at a dose that does not itself produce turning, significantly increased the contralateral rotation observed following a low dose of the specific D₂ agonist LY 171555. Doses of SKF 38393A or the D₂ agonist bromocriptine, which would themselves not induce turning, in combination produced a high rate of turning. These results suggest a synergistic interaction between D₁ and D₂ dopamine receptors in this system.

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: This work was supported by The Parkinson Foundation of Canada and the Medical Research Council.

¹: We thank Dr. Georgia Cottrell for advice and M.R. Peterson for assistance. SKF 38393A was a gift of Smith Kline and French. LY 171555 was a gift of Lilly Laboratories. Bromocriptine was a gift of Sandoz.

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Synergistic effects of D1 and D2 dopamine agonists on turning behaviour in rats

Abstract

Life Sci.

Eur. J. Pharmacol.

Bromocriptine in parkinsonism

Br. Med. J.

The classification of dopamine receptors: relationship to radioligand binding

Ann. Rev. Neurosci.

Behavioural correlations of dopamine receptor activation

Neurology

The Pharmacological Basis of Therapeutics

Synergistic effects of D₁ and D₂ dopamine agonists on turning behaviour in rats