[Effect of metoclopramide, dopamine receptor blocker, on the EOG light peak].
We studied the effects of metoclopramide hydrochloride (MTCL), a D2-selective dopamine receptor antagonist, on the electro-oculograms (EOGs) in 10 eyes of 5 healthy volunteers and on the electroretinograms (ERGs) in 6 eyes of 3 volunteers. MTCL was given intravenously after 15 minutes of dark adaptation. The L/D ratio of EOG was 2.13 +/- 0.14 (mean +/- SE) before the administration of MTCL. After the administration of MTCL, the dark-adapted EOG amplitudes increased transiently. MTCL significantly depressed the L/D ratio to 1.60 +/- 0.07 (p less than 0.01). The a- and b-wave amplitudes of the flash ERG decreased by 12% and 11% respectively. However, the OP2 and OP3 amplitudes of oscillatory potential increased by 23% and 19% respectively. The implicit times of all waves mentioned above tended to be prolonged. This study shows that a blockade of D2-dopamine receptor supresses the EOG light peak. Further investigations are needed to clarify the exact mechanism of this effect.
Maruiwa
F
F
Department of Ophthalmology, Miyazaki Medical College, Japan.
Kim
S D
SD
Nao-i
N
N
Sawada
A
A
D000328:Adult; D003623:Dark Adaptation; D018492:Dopamine Antagonists; D004585:Electrooculography / Q000187:drug effects*; D004596:Electroretinography; D005123:Eye / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008787:Metoclopramide / Q000494:pharmacology*; D009799:Ocular Physiological Phenomena; D010775:Photic Stimulation
D018492:Dopamine Antagonists; D008787:Metoclopramide