Effects of Glucose Administration on Development of Sclera in Chick Embryos.

OBJECTIVE: To determine the effect of glucose administration on the development of sclera in the chick embryo Gallus domesticus. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: Anatomy Department, CPSPRegional Centre, Islamabad, from January 2013 to January 2014. METHODOLOGY: The study was carried out in two main groups, control Aand experimental B, which were subdivided into three subgroups comprising 30 eggs each. The group Awas injected with normal saline (0.3 ml) in the egg albumen. The group B was injected with 0.3 ml of 5% w/v solution of glucose equivalent to 15 mg of glucose. Subgroups A1 and B1 were opened on day 10 of incubation. Subgroups A2 and B2 were sacrificed on day 12 of incubation. Eggs from subgroups A3 and B3 were opened on day 15 of incubation. Experimental subgroups were compared with matched control subgroups and quantitative data was analysed statistically. RESULTS: Administration of glucose resulted in changes in thickness of sclera. The mean thickness (µm) of sclera at day 10 of incubation was 43.54 ±2.45 in control subgroup and 43.03 ±5.86 in the experimental subgroup (p=0.673). The mean thickness (µm) of sclera at day 15 of incubation 77.48 ±8.32 in control subgroup and 73.99 ±8.62 in experimental subgroup (p=0.145). The mean number of chondrocytes/unit area of hyaline cartilage of sclera in day 10 was 17.40 ±1.44 control subgroup and 14.57 ±1.87 in the experimental subgroup (p < 0.001). The mean number of chondrocytes/unit area of hyaline cartilage of sclera on day 15 was 10.02 ±0.86 in the control subgroup and 9.54 ±0.59 in the experimental subgroup (p=0.025). There was disrupted ossicular formation indicating adverse effects on the development of bony sclera as well. CONCLUSION: Administration of glucose caused alteration in the histology of sclera in developing chick embryos.