Swelling tendency of rabbit cornea in organ culture medium

1992

Self Cite

A weight recording system (Medin & Davanger 1988, 1989), was used to demonstrate possible toxic damage of a medicament to the endothelium of rabbit corneas stored in organ culture. Seven corneas were stored in organ culture medium containing gentamicin (3.0 mg/ml). Seven other corneas stored in identical organ culture medium without gentamicin served as controls. The corneas were followed with weight recordings for up to 76 h. A toxic effect of gentamicin was demonstrated by a rapid weight increase in the corneas stored in the presence of gentamicin. After 5.3 h there was a significant difference (P = 0.0002) between the average weights of the two groups, and this difference increased during the following 2-3 days. Corneas from the two groups were also examined by light microscopy and scanning electron microscopy. There was good accordance between the weight recordings and the morphology. The weight recording system detects clearly the toxic effect of gentamicin (3.0 mg/ml).

Section: Discussioncontrasting

confidence: 54%

A method for registration of toxic drug effects on corneal endothelium

1992

Self Cite

“…The influx through the peripheral edge and through the anterior f posterior surfaces may be calculated separately, because the ratio between these two parts of the button surface is different at different button diameters (Medin & Davanger 1988, 1989a. Our data do not allow a separate calculation of the influx through the anterior and through the posterior surface, because the ratio between these two parts of the total surface does not change with changing button diameters.…”

Section: Discussionmentioning

confidence: 80%

“…The swelling tendency is counteracted by the barrier effect of the cell layers, and also by the pump effect of the endothelial cells (Hull et al 1986;Medin & Davanger 1988, 1989a. The net uptake of water is thereby reduced.…”

mentioning

confidence: 95%

The swelling of cornea in bank cultivation. The role of barriers and peripheral edge

Davanger

1991

Self Cite

The swelling of a rabbit cornea in organ culture is caused by influx of fluid via the surface. Data regarding the weight increase rates during the first 4 h of corneal buttons with different diameters, have been used to calculate the net influx per mm2 per h via the anterior + posterior surfaces on one hand, and via the peripheral edge on the other hand. In fresh corneas the contribution to the corneal swelling, of the net fluid uptake via the anterior + the posterior surfaces, is negligible. The influx via the peripheral edge is about the same in fresh and freeze treated buttons. For freeze treated corneas, the resistance for fluid transport via the anterior + posterior surfaces seems to be 4 times higher than the resistance for transport via the peripheral edge. This result indicates that the Descemet's membrane and the Bowman's layer may have some barrier effect. An alternative or supplementary explanation is that, at least in swollen corneas, there may be reduced resistance to fluid flow along the corneal plane as compared with the flow vertical to this plane.

“…The rate of percentage weight change, as calcukdted by derivation of equation (2), with the parameters presented in Table 2 and in Medin & Davanger (1988, 1989.…”

Section: Discussionmentioning

confidence: 99%

“…When a rabbit cornea is placed in a culture me-694 dium for storage, it increases in weight (Medin & Davanger 1988;Ehlers 1966). A breakdown or reduction of the corneal cell barriers may perhaps contribute to the weight increase.…”

mentioning

confidence: 99%

The cell barrier effect in rabbit corneas kept under eye bank conditions

Davanger

1989

Self Cite

The influence of endothelial cell pumping and of cell barrier functions on cultivated corneas has been studied by comparing the rate of weight increase in freeze-treated, ouabain-treated and fresh corneas. Inhibition of the endothelial cell pump activity increased the swelling rate from 0.5% of start weight per h (fresh corneas) to about 2% per h (ouabain-treated corneas), as measured after 24 h in culture medium. The cell barrier effect was estimated by comparing the swelling rate of ouabain-treated corneas after 24 h, and the swelling rate of freeze-treated corneas with the same swelling pressure. The values are 2 and 9.5% per h, respectively. The swelling rate of freeze-treated corneas with different button diameters was found to increase with decreasing corneal button diameter.