F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología
Abstract
Although busulfan, a bifunctional alkylating
agent, is known to induce cataracts in infant rats, the full
nature of busulfan-induced ocular lesions has not yet
been shown. In order to clarify this point, 6-day-old rats
were treated with a single dose of 20 mg/kg busulfan and
the ocular tissue was histopathologically and
immunohistochemically examined at 1, 2, 4, 7 and 12
days after treatment (DAT). As a result, in the nuclear
layer (NL) of the peripheral retina, apoptotic cells
significantly increased at 1 DAT and peaked at 2 DAT
when cell proliferating activity was depressed. At 4
DAT, the NL showed wavy deformation with formation
of rosette-like structures, and these changes progressed
prominently at 12 DAT. In addition, a significant
reduction in the retinal thickness due to decreased
thickness of NL or inner NL was detected at 2 and 4
DAT. On the other hand, in the germinative zone of the
lens equator, apoptotic lens epithelial cells significantly
increased from 2 to 7 DAT, resulting in partial loss of
lens epithelial cells at 7 and 12 DAT. At 12 DAT,
prominent swelling and vacuolation of lens fibers were
observed in the area from the equatorial zone to the
posterior pole, indicating the development of cataract.
The present results strongly suggest that prominent
apoptosis in component cells was the initial and essential
event underlying the developpment of busulfan-induced
ocular lesions in infant rats