Neural activity from the acutely infected HSV-1 rabbit cornea

Herpes simplex virus type 1 (HSV-1) infections of the human cornea are often accompanied by abnormal sensations. In this study, a combination of physiological and structural methods was used to examine the innervation of the corneas of rabbits with HSV-1 lesions of varying severity. Degeneration of the plexiform neural layer adjacent to dendritic lesions and surrounding normal neurology provided a basis for the limited physiological changes. Extensive degeneration of the corneal innervation at all levels occurred within the anesthetic area of the geographic lesion. Abnormal physiological activity characterized by hyperexcitability and loss of stimulus specificity were included in the physiological profile. Collateral sprouts seen in the geographic lesion were suggested as an anatomical substrate for the abnormal neural activity. Thus, the neural changes could be associated with the severity of HSV-1 lesions.