Effect of PD I administration on dopamine receptors mRNAs expression in the lesioned striatum of PD rat model

Abstract

To study the effect of PD I administration on dopamine receptors (DR₁, DR₂) mRNAs expression in the lesioned striatum of the PD rat model and confirm if PD I has the effect of dopamine receptor agonist. The PD rats with unilateral 6-hydroxydopamine lesioned were administrated with PD I, L-dopa methyl/benserazide, L-dopa methyl/benserazide/PD I, normal saline respectively for 4 weeks and their behavioral changes were observed. Then the rats were sacrificed and RT-PCR technique was used to detect changes of dopamine receptors (DR₁, DR₂) mRNAs expression in the ipsilateral striatum 1 day after the last treatment. The results showed that treatment with PD I plus L-dopa resulted in a stable contralateral rotation behavior; treatment with L-dopa resulted in a progressively increased contralateral rotation behavior. Rotation behavior induced by anhydromorphine decreased with PD I or PD I plus L-dopa treatment. Treatment With L-dopa or PD I plus L-dopa, up-regulation of DR₁ mRNA and down-regulation of DR₂ mRNA were observed in the ipsilateral striatum which were more obvious than that treated with PD I or vehicle (P<0.05). It was concluded that long-term treatment with PD I could alleviate the behavior of PD rats. PD I had no apparent effect on the dopamine receptors (DR₁, DR₂) mRNAs expression in the ipsilateral striatum and the PD I has no agonist effect on dopamine receptors.

Keywords

Parkinson's disease / 6-hydroxydopamine / dopamine receptor

References

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