The effect of interleukin-1alpha on outflow facility in rat eyes.

PURPOSE

The authors investigated whether regulation of the trabecular extracellular matrix turnover rate and remodeling plays an important role in decreasing outflow resistance by determining the effect of intracamerally given interleukin-1alpha, a known stimulator of the expression of trabecular matrix metalloproteinases, on outflow facility of albino rat eyes.

MATERIALS AND METHODS

Forty normal albino rats (Sprague-Dawley), weighing 250 to 300 g, were studied. Rats were anesthetized by intraperitoneal pentobarbital sodium (30 mg/kg) injection. The rats were separated into four groups and given 5, 10, 25, or 50 units of interleukin-1alpha injected intracamerally in one eye. Bovine serum albumin in phosphate-buffered saline, which was used to dissolve the interleukin-1alpha, was injected in the fellow eye as a control. Outflow facility was measured by two-level constant pressure perfusion 1, 3, and 7 days after injection.

RESULTS

The eyes treated with 50 units of interleukin-1alpha showed a statistically significant increase of outflow facility by 37% compared with the contralateral control eyes 3 days after injection, but returned to normal levels in 7 days. The eyes treated with 5, 10, 25, or 50 units of interleukin-1alpha showed outflow facility increases of 12%, 20%, 39%, and 37%, respectively, 3 days after injection.

CONCLUSION

Interleukin-1alpha increased the outflow facility, supporting the hypothesis that regulation of trabecular meshwork extracellular matrix plays a role in trabecular outflow resistance.