ABSTRACT
The effect of salmon calcitonin on the maturation of the regenerate bone was assessed in an experimental model in rabbits. Twenty-six New Zealand White male rabbits, approximately 5 months old and weighing 3 to 3.5 kg, were subjected to a mid-diaphyseal tibial osteotomy. After 5 days, the right tibia was lengthened gradually at a rate of 0.375 mm every 12 hours, for 10 days. Ten international units of salmon calcitonin were administered daily subcutaneously to the study group (14 animals), whereas the animals of the control group (12 animals) were injected with a placebo, for the duration of the experiment. The bone mineral density of the regenerate bone was assessed on Days 20, 35, 45, and 55 of the experiment, in both groups, using dual energy xray absorptiometry. No statistical significant difference was found in the dual energy xray absorptiometry measurements between the study and control groups regarding the change of the bone mineral density of the new bone relative to a preoperative baseline measurement. Characteristic time-related changes were observed in the bone mineral density of the regenerate bone during its maturation, which proved to be identical in both groups. It seems that the administration of calcitonin does not enhance regenerate bone mineralization rate and tendency during bone lengthening.
Subject(s)
Bone Density/drug effects , Calcitonin/administration & dosage , Disease Models, Animal , Osteogenesis, Distraction , Tibia/drug effects , Absorptiometry, Photon , Analysis of Variance , Animals , Bone Regeneration/drug effects , Calcitonin/pharmacology , Drug Administration Schedule , Drug Evaluation, Preclinical , Injections, Subcutaneous , Leg Length Inequality/diagnosis , Leg Length Inequality/therapy , Male , Osteogenesis, Distraction/methods , Rabbits , Time FactorsABSTRACT
Chemokines are involved in a number of pathophysiological conditions, such as inflammatory processes and are divided in two major subfamilies, C-X-C and C-C chemokines. The C-C chemokines are monocyte chemotactic protein 1-2-3-4-5, while C-X-C chemokines include MIP-2, IL-8, etc. We studied the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue and serum in Trichinella spiralis infected mice treated and not treated with 4-deoxypyridoxine, a potent Vit. B6 antagonist which inhibits humoral and cellular immune response. MCP-1 and MIP-2 were measured in homogenized tissue and serum and determined by a specific ELISA. Here we found the levels of MCP-1 and MIP-2 in diaphragmatic and intercostal muscle tissue of T. spiralis infected mice were significantly increased after 10 days and peaked on day 20 post-infection; however, the levels of MIP-2 in mice treated with 4-DPD was lower than that of untreated mice at day 20. MCP-1 also peaked at days 20 and 40. Animals treated with 4-DPD also inhibited the production of MCP-1, compared with untreated animals. The maximum inhibition was at day 40. These inhibitory effects on MIP-2 and MCP-1 were also repeated in the serum determinations, but were not significant. This study demonstrates that MIP-2 and MCP-1 are stimulated in serum and tissue of T. spiralis infected mice and 4-DPD-treated animals significantly inhibited them.
