Fosfatase ácida resistente ao tartarato como biomarcador do metabolismo ósseo no cão / Tartrate-resistant acid phosphatase as a biomarker of bone turnover in dog

Values of serum tartrate-resistant acid phosphatase ( TRAP) activity were obtained in adult dogs and its biological variability was assessed. Nine healthy skeletally mature Portuguese Podengo dogs were used for the determination of TRAP, total and bone alkaline phosphatase serum activities, and also to study their relationship with serum minerals, namely calcium (Ca), phosphorous (P), and magnesium (Mg). The serum TRAP activity was 2.19±0.56IU/mL, with intra-individual variation of 18.3 percent and inter-individual variation of 25.6 percent. Significant correlations were observed between serum TRAP activity and Ca (r=-0.3431; P<0.05), Ca and Mg (r=-0.787; P<0.01), and TRAP and Mg (r=0.397; P<0.05). The results indicate that serum TRAP activity in dog could be of great value in research and in clinical practice, providing complementary non-invasive information on bone metabolism.

Determinaram-se os valores da atividade da fosfatase ácida resistente ao tartarato (FART) e avaliou-se a sua variabilidade biológica. Neste estudo, foram utilizados nove cães adultos e saudáveis de raça Podengo Português para as determinações das atividades da FART, da fosfatase alcalina total, da isoenzima óssea da fosfatase alcalina e da concentração dos minerais séricos - cálcio, fósforo e magnésio. A atividade sérica obtida da FART foi de 2,19±0,56 UI/mL, com uma variação intra-individual de 18,3 por cento e interindividual de 25,6 por cento. Foram observadas correlações significativas ao longo do tempo entre FART e cálcio (r=-0,3431; P<0,05), entre FART e magnésio (r=0,3974; P<0,05) e entre cálcio e magnésio (r=-0,787; P<0,01). Os resultados indicam que este marcador de reabsorção óssea pode ser de grande valor na prática clínica e na investigação e, ainda, ser utilizado como um método auxiliar não invasivo para avaliação do metabolismo ósseo.

Assessment of markers of bone formation under controlled environmental factors and their correlation with serum minerals in adult sheep as a model for orthopaedic research.

Eighteen healthy skeletally mature (3 years old) ewes, with an average weight of 45 kg, of the Portuguese Churra da Terra Quente breed were used to evaluate the normal values of total and bone-specific isoform of alkaline phosphatase serum activities (ALP and BALP, respectively) and serum osteocalcin (OC) and their correlation with the serum minerals - calcium (Ca), phosphorus (P), magnesium (Mg) and ionized calcium (Ca(2+)). The sheep were maintained under controlled environmental conditions (constant diurnal photoperiod cycle and identical husbandry and feeding) for six weeks before the collection of the blood samples. The measurement of the total ALP and serum minerals was performed with automated biochemistry analysers using the BioMérieux kits, the serum electrolyte Ca(2+) Diametrics Medical, Inc specific cassettes and the BALP and OC METRATM kits from QUIDEL Corporation. The mean +/- standard deviation values obtained were: total ALP 90.17 +/- 85.72 U/L, BALP 15.0 +/- 5.44 U/L, ratio BALP/ total ALP 29.28 +/- 24.22, OC 13.02 +/- 1.87 ng/mL, Ca 2.57 +/- 0.37 mmol/L, P 2.13 +/- 0.42 mmol/L, Mg 1.04 +/- 0.13 mmol/L, Ca(2+) 1.29 +/- 0.04 mmol/L. Significant correlations were observed between the total ALP and Ca (r = 0.5939; P = 0.05) and OC and Ca (r = 0.5706; P = 0.05). Reference to the serum values of bone turnover parameters in sheep could be of great value in research and could provide complementary non-invasive information on the bone healing process, particularly with regard to obtaining an early prognosis of fracture healing.