Ultrastructural changes in the developing chicken cornea following caffeine administration.

Caffeine is one of the most frequently consumed psychoactive substances. It has been known for many years that caffeine at high concentrations exerts harmful effects on both women's and laboratory animals' fertility, moreover it may impair normal development of many organs in the prenatal period. So far there have been few studies performed that demonstrate teratogenic effects of caffeine on structures of the developing eye, particularly the cornea. The aim of the study was to show ultrastructural changes in the developing cornea, as the effect of caffeine administration to chicken embryos. The experimental materials were 26 chicken embryos from incubated breeding eggs. Eggs were divided into two groups: control (n=30) in which Ringer liquid was administrated, and experimental (n=30) in which teratogenic dose of caffeine 3.5mg/egg was given. In 36th hour of incubation solutions were given with cannula through hole in an egg shell directly onto amniotic membrane. After closing the hole with a glass plate and paraffine, eggs were put back to incubator. In 10th and 19th day of incubation corneas were taken for morphological analysis with a use of electron microscopy. Administration of caffeine during chicken development causes changes of collagen fibers of Bowman's membrane patterns and of the corneal stroma but it also changes proportion of amount of collagen fibers and of the stromal cells.