Effects of sympathetic denervation on the hyaluronan content of the anterior segment in the normal and traumatized rabbit eye.

PURPOSE To determine whether there is any involvement of sympathetic nerves in the regulation of ocular hyaluronan production in the normal and traumatized rabbit iris. METHODS Unilateral sympathetic denervation was performed by removing the right superior cervical ganglion. Hyaluronan concentrations in the iris and aqueous were measured with a radiometric assay at various time intervals after denervation. Peripheral iridectomy was also performed in both denervated and non-denervated eyes. RESULTS Hyaluronan concentrations in the iris tissue after denervation were observed to have increased after 1 day, reaching a peak of 129.6 +/- 5.7 microg/g wet weight at day 3. Two weeks later, hyaluronan concentrations had fallen back to normal levels. Ocular trauma with peripheral iridectomy in denervated eyes caused an increase of hyaluronan content of up to 253.5 +/- 30.5 microg/g wet weight, which was not significantly different from hyaluronan concentrations observed after the same trauma in non-denervated eyes. CONCLUSION Cervical sympathetic denervation results in a moderate increase of the hyaluronan content in the rabbit iris and does not appear to influence the hyaluronan response of the iris to trauma.