Presynaptic actions of piribedil on the cardiovascular system of the pithed rat.
The influence of piribedil on cardiovascular sympathetic responses has been studied in the pithed rat. Piribedil (0.3-1 mg kg-1) inhibited the increases of diastolic blood pressure induced by spinal cord electrical stimulation at the level Th5-L4. This effect was reversed by sulpiride (0.3 mg kg-1) but not by yohimbine (0.3 mg kg-1). The cardiovascular responses induced by noradrenaline were unaffected by piribedil (0.3-1 mg kg-1). However piribedil (0.3-1 mg kg-1) did not modify the heart rate increase induced by spinal cord electrical stimulation at the C7-Th1 level. These results suggest that piribedil inhibits the vascular sympathetic transmission in the pithed rat via stimulation of presynaptic dopamine receptors.
Moron
A
A
Cuffi
L
L
Vila
E
E
Badia
A
A
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D003655:Decerebrate State; D004558:Electric Stimulation; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D010891:Piribedil / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000502:physiology
D010879:Piperazines; D010891:Piribedil