Effects of intravitreal injection of botulinum toxin on the electroretinogram of rats.
The retinal toxicity of botulinum toxin A (BTA) was electroretinographically studied in rats. Sixteen rats were injected intravitreally with 10 ng of BTA. A response-amplitude series was recorded before and 1, 6, 13 and 21 days after the injection of BTA. BTA did not alter the amplitude and the peak latency of the a-wave. The amplitude of the b-wave was not changed except for 2 rats, in which the b-wave was diminished. The peak latency of the b-wave was significantly prolonged after injection of 10 ng BTA (p < 0.05). Except for these latter 2 rats, the results indicated that the dosage used therapeutically appears to have no deleterious effect on retinal integrity or function at least in the short term, but multiple injections or higher doses of BTA could alter retinal function.
Li
S
S
Department of Ophthalmology, Chiba University School of Medicine, Chiba, Japan.
Mizota
A
A
Adachi-Usami
E
E
D000818:Animals; D001905:Botulinum Toxins / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004596:Electroretinography / Q000187:drug effects; D005260:Female; D007267:Injections; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D012160:Retina / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors; D014822:Vitreous Body
D001905:Botulinum Toxins