Bone Abstracts

Objectives: This study thus was aimed at investigating of ultrastructure of the hipbone biomineral in rats with defect in tibia after 60-day per os administration of sodium benzoate (SB) in various concentrations and mexidol (M).

Methods: The experiment involved 280 male thoroughbred rats with initial body weight of 200–210 g. The 1st group (K) comprised animals that received daily per os 1 ml of 0.9% solution of NaCl, the 2nd and the 3rd groups (SB1 and SB2) received per os 1 ml of SB in dosage of 500 or 1000 mg/kg of body weight, the 4th group (D) comprised animals with defect in both tibiae made when in groups 2 and 3 SB was discontinued. The 5th and the 6th groups (DSB1 and DSB2) comprised the rats who received SB and had defects in tibiae also made after SB discontinue and the 7th and 8th groups also received M in dosage of 50 mg/kg (DSB1M and DSB2M). Observation terms constituted 3, 10, 15, 24, and 45 days after discontinue of experimental influences. For testing of bone biomineral purposes we used X-ray scatter analysis.

Results: Fracture modeling (2.2 mm defect in tibia shaft) on the background intake of SB comparing with group without intake of SB accompanied by enlargement of elementary cells from the 3rd to the 15th day and microtexture coefficient decrease on the 3rd day. It follows that the longest violation occurs of elementary cells forming of hipbone biomineral. In dosage of SB of 500 mg/kg these deviations were respectively 6.68 and 0.14–0.21%, and in dosage of SB 1000 mg/kg – 7.45% and 0.16–0.22%. Defect modeling on the background intake of SB and M in dosage reduces adverse effects of SB on the hipbone biomineral ultrastructure by only 3rd day of observation. With SB dosage 500 mg/kg these accompanied by reducing the size of elementary cells comparing with group without intake of M on 0.15%, and with SB dosage 1000 mg/kg – reducing the size of elementary cells on 0.11% and microtexture coefficient decrease on 3.87% (P<0.05 in all cases).

Conclusions: Defect in tibia after 60-day administration of SB is accompanied by destabilization of ultrastructure of bone biomineral compared with the group without SB. Under dosage of SB of 1000 mg/kg, the severity of the changes was larger than that at a dose of 500 mg/kg. The simultaneous administration of SB and M at dosage of 50 mg/kg smoothed destabilization of ultrastructure of bone biomineral after application defect of the tibia.