Determination of the decalcification time of sternum, knee joint and nasal cavity specimens from mice, gerbils and hamsters

Procedure of decalcification necessary for histology of bone tissue. Decalcification is the procedure of removing minerals from the bone organic matrix. Solutions of varying acids usually used as a decalcification solution. Whole bone or piece that had been cut out preliminary are can be sampled for decalcification. Study of a knee joint and nasal cavity specimens usually uses in preclinical research. Also, for the study of bone marrow, a sternum often is sampled. The cutting out of small piece often leads to the destruction of the sample, because of their small size. Thus, whole maxilla, whole sternum and knee joint to include femur, fibula and tibia are more often sampled for research. This article describe a time of decalcification above-mentioned specimen that were sampled from mice, gerbils and hamsters. Solutions of formic and hydrochloric acids were used as the decalcification solution. The decalcification solution were changed every other day. The severity of decalcifications and specimen readiness for histology procedure were evaluated by gravimetric method. We found that the trends in mass change and decalcification time change were the same for all animal types noted above. In none case, the absolute severity of decalcification was reached, within 10 days. However, the severity of decalcification of whole specimens of bone was sufficient to make a quality histological slide. All specimens achieved the sufficient severity of decalcification on 4th day. This period allows to evaluate the morphology of the respiratory and olfactory epithelium of the nasal cavity, joint cartilage and bone marrow cells. The period of decalcification can be extended to 7 days, if anatomic and topographic features and them the best quality more important. The period of decalcification more 7 days leaded to irreversible change of cell morphology. Cells had poor detalization, cell nuclei were stained with hematoxiline badly, cell borders were unclear.