Effects of dopamine antagonists on retinal B-wave recovery after retinal ischemia.

Retinal ischemia was developed by occlusion of the central retinal artery for 30 minutes. The artery was reperfused thereafter, and the recovery of the b-wave amplitude was determined as an indication of the recovery of retinal function after ischemia. Following ischemia, it was found that dopamine antagonists, including chlofluperol, metoclopramide, trifluperol and droperidol, increased in b-wave amplitude recovery significantly over the control b-wave recovery. Similar effects were observed with haloperidol and loxapine, but to a lesser extent. The results correlated well with the improvement of retinal blood flow by these dopamine antagonists (4,5). Neither floropipamide, a dopamine antagonist, nor bromocriptine, a dopamine agonist, affected the b-wave recovery after ischemia. These results also correlate well with the inability of these agents to increase the retinal blood flow measured by the microsphere technique (4,5). These findings suggest that most of the dopamine antagonists, with the exception of floropipamide, could be used for the treatment and/or prevention of ischemic retinopathy.