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Published on: November 25, 2014
LHRH antagonizes yawning and genital grooming induced by apomorphine in rats
1Departamento Preclinicas, Facultad de Medicina, Universidad de Chile, Santiago.
Abstract:
The effects of the pretreatment with LHRH on the behavioral effects induced by low doses of apomorphine were studied in male rats. Three doses of apomorphine (31.25, 62.50 and 125 micrograms/kg) were subcutaneously administered two hours after LHRH 100 micrograms/kg or solvent SC treatment. Apomorphine induced repeated episodes of yawning and genital grooming. Pretreatment with LHRH abolished or reduced yawning and genital grooming induced by the three doses of apomorphine, suggesting that the peptide could induce subsensitivity of DA receptors responsible for yawning and genital grooming.
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