ABSTRACT
Abstract Objective To verify how the combined administration of alendronate (ALN) and vitamin D3 (VD) acts on the bone microarchitecture in rats with glucocorticoid-induced osteoporosis. Methods The experiment used 32 90-day-old female Wistar rats weighing between 300 and 400g. The induction of osteoporosis consisted of intramuscular administration of dexamethasone at a dose of 7.5 mg/kg of body weight once a week for 5 weeks, except for the animals in the control group. The animals were separated into the following groups: G1 (control group without osteoporosis), G2 (control group with osteoporosis without treatment), G3 (group with osteoporosis treated with ALN 0.2 mg/kg), G4 (group with osteoporosis treated with VD 10,000UI/500μL), and G5 (group with osteoporosis treated with ALN þ VD). The right femurs of the rats were fixed in 10% buffered formaldehyde, decalcified, and processed for inclusion in paraffin. Histological sections were stained with hematoxylin-eosin for histomorphometric analysis. Cortical thickness and medullary cavity were measured in cross-sections. Results There was a statistical difference (p< 0.05) between groups G3 and G5 compared with the positive control group (G2), both related to the measurement of cortical thickness and to the total diameter of the bone. In the evaluation of the spinal area, only the G3 group has shown to be statistically different from the G2 group. Conclusion Concomitant treatment with daily ALN and weekly VD is effective in preventing glucocorticoid-induced bone loss. However, there was no difference between the therapy tested and treatment with ALN alone.
Resumo Objetivo Verificar como a administração conjunta de alendronato de sódio (ALN) e vitamina D3 (VD) atua na microarquitetura óssea em ratas com osteoporose induzida por glicocorticoide. Métodos O experimento utilizou 32 ratas da linhagem Wistar, com peso médio de 300 a 400g, com 90 dias de vida. A indução da osteoporose consistiu na administração de dexametasona na dose de 7,5 mg/kg de peso corporal, por via intramuscular, 1 vez por semana durante 5 semanas, à exceção dos animais do grupo controle. Os animais foram distribuídos nos seguintes grupos: G1 (grupo controle sem osteoporose), G2 (grupo controle com osteoporose sem tratamento), G3 (grupo com osteoporose tratado com ALN 0,2 mg/kg), G4 (grupo com osteoporose tratado com VD 10.000UI/500μL) e G5 (grupo com osteoporose tratado com ALN þ VD). Os fêmures direitos das ratas foram fixados em formol a 10% tamponado, descalcificados e processados para inclusão em parafina. Os cortes histológicos foram corados com hematoxilina-eosina para análise histomorfométrica. A espessura cortical e a cavidade medular foram medidas em cortes transversais. Resultados Houve diferença estatística (p< 0,05) entre os grupos G3 e G5 em relação ao grupo controle positivo (G2), tanto em relação à medida da espessura cortical quanto em relação ao diâmetro total do osso. Na avaliação da área medular, apenas o grupo G3 se mostrou estatisticamente diferente do grupo G2. Conclusão O tratamento concomitante com ALN diário e VD semanal é eficaz para prevenir a perda óssea induzida por glicocorticoide. No entanto, não houve diferença entre esta terapia testada e o tratamento apenas com o ALN.
Subject(s)
Animals , Rats , Osteoporosis/prevention & control , Vitamin D/therapeutic use , Alendronate/therapeutic use , MenopauseABSTRACT
The present study had the objective of obtaining information about fertility in rats treated with dexamethasone for 10 and 15 days consecutively, to polycystic ovaries, induced by constant illumination. It was used 40 albino rats (Rattus norvegicus albinus), aged 90 days, form the lineage Wistar, which were split, randomly, in four groups, each constituted of 10 animals, namely: Group I - rats kept in a clear/dark cycle for 12/12 hours, and after 100 days submitted to fertility evaluation (control); Group II - rats kept under constant illumination during 100 days and then submitted to fertility evaluation; Group III - rats kept under constant illumination during 100 days, then treated with dexamethasone for 10 days and submitted to fertility evaluation; Group IV - rats kept under constant illumination during 100 days, then treated with dexamethasone for 15 days and submitted to fertility evaluation. The results showed that the number of implanted sites was 38(G1), 37(G2), 32(G3) and 06(G4). The reduction in group IV was due to the high mortality during the experiment, probably because of the prolonged treatment with dexamethasone. These sites presented similar histological aspects. The macroscopic analysis of the neonates haven't shown any indication of malformation. Also, abortion haven't been observed. The treatment with dexamethasone for 10 days in rats does not affect the fertility and the development of the lungs, liver and kidneys of neonates, while the administration during 15 days leads to a high maternal mortality.
El estudio tuvo el objetivo de obtener informaciones sobre la fertilidad en ratas tratadas con dexametasona por 10 y 15 días seguidos, para ovarios poliquísticos, inducidos por iluminación constante. Se utilizó 40 ratas albinas (Rattus norvegicus albinus) con 90 días de edad, del linaje Wistar, las cuales fueron divididas, en cuatro grupos, cada uno constituido por 10 animales: Grupo I - ratas mantenidas en ciclo claro/oscuro de 12/12 horas, y después de 100 días sometidas a la evaluación de la fertilidad (control); Grupo II- ratas mantenidas bajo iluminación constante, durante 100 días, y luego sometidas a la evaluación de la fertilidad ; Grupo III - ratas mantenidas bajo iluminación constante, a lo largo de 100 días, y posteriormente tratadas con dexametasona por diez días, y sometidas a la evolución de la fertilidad; Grupo IV - ratas mantenidas bajo iluminación constante, durante 100 días, en seguida tratadas con dexametasona por 15 días, y sometidas a la evaluación de la fertilidad. Los resultados mostraron que el número de sitios implantados fue 38(GI), 37(G2), 32(G3), y 06(G4). La reducción en el grupo IV fue como consecuencia de la alta mortalidad durante la experiencia, probablemente en función del largo tratamiento con dexametasona. Esos sitios presentaron aspectos histológicos semejantes. El análisis macroscópico de los neonatos no mostró ningún vestigio de malformación. Tampoco fueron observados abortos. El tratamiento con dexametasona por 10 días en ratas, no afecta la fertilidad y el desarrollo de los pulmones, hígado y riñones de neonatos, mientras que la administración por 15 días lleva a una alta mortalidad materna.