Acute ethanol intoxication can inhibit leucocyte mobilization in the corneal wounds

Abstract

The susceptibility to various kinds of infection in alcoholics has been attributed to the impairment of leucocyte functions by ethanol. As the possibility of corneal injury is ever present in the intoxicated person we wished to study the pattern of leucocyte mobilization into wounds of the cornea (an avascular tissue) of rabbits intoxicated with alcohol. Thirty-six rabbits were divided into two equal groups. One group (alcohol group) was injectedintravenously with 25% ethanol (20 ml/kg) to produce intoxication. The other group (control group) did not receive the agent and was anaesthetized with intravenous pentobarbital sodium. Identical non-penetrating central and peripheral trephine incisions (4 mm in diameter and 0·1 mm in depth) were made in both corneas of each rabbit. Two, 4 or 6 hr following the injury, cellular samples were obtained by pressing a cover slip on the surface of the lesions (the impression technique). The animal was then killed for corneal histology. Leucocyte (PMN) counts were made on samples obtained by both the impression and histological techniques. In the alcohol group, the average blood alcohol level in the animals at the time of killing was about 400 mg/100 ml. At each of the three time periods, during which the cornea remained avascular, the alcohol group showed a significantly lower number of PMNs in the corneal lesions (both central and peripheral) as compared to the corresponding lesions in the control group ( P <0·1–0·001). The total and differential blood leucocyte counts in both groups were similar. Our results showed that alcohol inhibits mobilization of PMNs in corneal wounds at least for 6 hr following injury.