Evaluation of a commercial recombinant tissue-type plasminogen activator preparation in the subretinal space of the cat
J. D. Benner, L. S. Morse, C. A. Toth, M. B. Landers 3rd and L. M. Hjelmeland
Department of Ophthalmology, University of California, Davis, Sacramento 95616.
To explore the feasibility of using human recombinant tissue-type
plasminogen activator in the management of subretinal hemorrhage, we
examined the toxic effects of a commercial preparation of human recombinant
tissue-type plasminogen activator in the subretinal space of the
holangiotic retina of the cat. Various concentrations of human recombinant
tissue-type plasminogen activator and controls were infused into the
subretinal space with a glass micropipette (40- to 60-microns tip) to form
a retinal bleb. Concentrations from 2.5 mg/L to 200 mg/L were well
tolerated without ultrastructural toxic effects, while 1000 mg/L of human
recombinant tissue-type plasminogen activator caused severe, irreversible
toxic effects to the photoreceptor-retinal pigment epithelium complex. This
toxic effect appeared to be due to the carrier vehicle rather than the
human recombinant tissue-type plasminogen activator protein itself. Our
results demonstrate that commercially prepared human recombinant
tissue-type plasminogen activator can be safely used in the subretinal
space of the cat with the range necessary for fibrinolysis.
