Bone Abstracts

Objectives: The study is aimed at investigation of ultrastructure of biomineral of the ramius of mandible (BRM) in rats after application of sodium glutamate (SG) and exposure to ionizing radiation (IR), and finding possibility of medication with Spirulina (SP).

Methods: The experiment involved 240 rats with body weight of 180–200 g. The animals were distributed into eight groups as follows: intact animals for the controls, animals that received per os SG in dosage of 30 mg/kg daily for 60 days, animals exposed to IR (total four Grey in four sessions), received Sp in dosage of 250 mg/kg, combined SG and IR, SG and Sp, Sp and IR, and all three agents simultaneously. The animals were withdrawn from the experiment by the 1st, the 7th, the 15th, the 30th, and the 60th day after cessation of experimental influences by means of anaesthetized decapitation. For testing of BRM, we used X-ray scatter analysis.

Results: Sixty-day SG intake in dosage of 30 mg/kg results in instability of crystal lattice of BRM yet lattice gradually restores after the 15th day of observation. By the first day after SG discontinue, microtexture coefficient decreased in comparison with the control group by 4.40%. Sixty-day exposure to IR also results in instability of crystal lattice of BRM, which persists up to the 30th day of observation though restoration is insignificant. By the first day after IR discontinue, microtexture coefficient decreased in comparison with the control group by 4.68%. Combined action of SG and IR affects crystal lattice of BRM to a greater extent than those two taken apart and crystal lattice fails to restore in this case. By the first day after SG and IR discontinue, microtexture coefficient decreased in comparison with the group with only SG intake by 4.86%. Application of Sp in dosage of 250 mg/kg reduces negative effects of SG and IR on crystal lattice of BRM. Restoration of crystal lattice of BRM (i.e. order degree increase and widening of exchange area) was also faster yet correction efficiency for combined influences was lower than for separate influences.

Conclusions: Sixty-day application of SG in dosage of 30 mg/kg and exposure to IR (total four Grey in four sessions) and their combined action results in instability of crystal lattice of BRM that expands even to readaptation period. This fact urges searching for medication and prophylactic measures for such a state. According to our findings Sp in dosage of 250 mg/kg well satisfies this demand.