Rabbit corneas kept in a standard tissue culture medium, were continua
lly exposed to ouabain 10(-3) M, and cultivated for 2, 3, and 4 days.
The endothelium was still intact with a complete cell cover after 2 da
ys of ouabain exposure. Total destruction of the endothelium was found
in the corneas cultivated for 3 and 4 days. The corneal epithelium, h
owever, appeared to be unaffected. Other rabbit corneas were exposed f
or three days to ouabain concentrations of 10(-4) M, 10(-5) M, 10(-6)
M, 10(-7) M, 10(-8) M, and 0 M. The corneas exposed to 10(-4) M demons
trated total endothelial cell damage. The specimens exposed to concent
rations from 10(-5) M to 10(-8) M, presented dose dependant endothelia
l impairment as compared with the control corneas (0 M). Tracer experi
ments showed that the endothelial barrier was intact as long as there
was a continuous cell cover, as estimated by light, transmission and s
canning electron microscopy.