Efeitos do cloreto mercuroso sobre o desenvolvimento do tecido ósseo : propriedades físicas, químicas e biomecânicas do fêmur de ratos.
Resumen
Because of the lack of data about the mercury influence on bone metabolism it is important to
investigate the bone parameters that can be affected by its effects. The aim of this study was
to evaluate the physical and biomechanical bone alterations in adult rats contaminated with
mercurous chloride during their development. The animals were separated in experimental
and control groups: 9 male rats treated with saline 0.9% (0.1 ml/100g BW) and 16 male rats
treated with mercurous chloride (1.25mg/kg BW) during 60 days, 5 days/week, by the
stomacal gavage. After that, the animals were sacrificed and the right femur was dissected.
The body weight, femoral length and thickness of femoral diaphysis were measured. The
mechanical properties (maximum and failure forces, stiffness and yield) of femurs were
evaluated by the tree-point bending test using the universal machine Instron model 4444. The
bone volume was estimated by the Archimedes Principle. The wet and ash weight were also
determined. The weight, length and major and minor diameters of the femurs were not
different between the groups; however the length and the major diameter showed tendency to
decrease. There was an increase (p=0,0460) of bone density of the contaminated animals.
The mineral density and the mechanical properties were not different between the both
groups. The dose of mercurous chloride used had little effect on bone development. It was
observed a tendency of higher values of bone biomechanical properties and a decrease of the
biometric values of the contaminated group. This would characterize a more resistant bone in
spite of a lower mineral content.