RESUMEN
ABSTRACT Introduction: Digital radiography (DRx) may provide a suitable alternative to investigate mineral and bone disorder (MBD) and loss of bone density (BD) in rodent models of chronic kidney disease (CKD). The objective of this study was to use DRx to evaluate BD in CKD rats, and to evaluate the correlation between DRx findings and serum MBD markers and bone histomorphometry. Methods: Uremia was induced by feeding Wistar rats an adenine-enriched diet (0.75% for 4 weeks/0.10% for 3 weeks); outcomes were compared to a control group at experimental weeks 3, 4, and 7. The following biochemical markers were measured: creatinine clearance (CrC), phosphate (P), calcium (Ca), fractional excretion of P (FeP), alkaline phosphatase (ALP), fibroblast growth factor-23 (FGF-23), and parathyroid hormone (PTH). DRx imaging was performed and histomorphometry analysis was conducted using the left femur. Results: As expected, at week 7, uremic rats presented with reduced CrC and higher levels of P, FeP, and ALP compared to controls. DRx confirmed the lower BD in uremic animals (0.57±0.07 vs. 0.68 ± 0.06 a.u.; p = 0.016) compared to controls at the end of week 7, when MBD was more prominent. A severe form of high-turnover bone disease accompanied these biochemical changes. BD measured on DRx correlated to P (r=-0.81; p = 0.002), ALP (r = -0.69, p = 0.01), PTH (r = -0.83, p = 0.01), OS/BS (r = -0.70; p = 0.02), and ObS/BS (r = -0.70; p = 0.02). Conclusion: BD quantified by DRx was associated with the typical complications of MBD in CKD and showed to be viable in the evaluation of bone alterations in CKD.
RESUMO Introdução: A radiografia digital (RxD) pode representar uma alternativa adequada para investigar o distúrbio mineral e ósseo (DMO) e a perda de densidade óssea (DO) em modelos de roedores da doença renal crônica (DRC). O objetivo deste estudo foi utilizar a RxD para avaliar a DO em ratos com DRC, e avaliar a correlação entre os achados da RxD e marcadores séricos de DMO e histomorfometria óssea. Métodos: A uremia foi induzida pela alimentação de ratos Wistar com dieta enriquecida com adenina (0,75% por 4 semanas/0,10% por 3 semanas); os resultados foram comparados com um grupo controle nas semanas experimentais 3, 4 e 7. Os seguintes marcadores bioquímicos foram medidos: clearance de creatinina (CCr), fosfato (P), cálcio (Ca), fração excretada de P (FeP), fosfatase alcalina (ALP), fator de crescimento de fibroblastos-23 (FGF-23) e paratormônio (PTH). A imagem da RxD foi obtida e a análise histomorfométrica foi realizada com o fêmur esquerdo. Resultados: como esperado, na semana 7, os ratos urêmicos apresentaram redução do CCr e níveis mais altos de P, FeP e ALP em comparação aos controles. A RxD confirmou a menor DO em animais urêmicos (0,57 ± 0,07 vs. 0,68 ± 0,06 u.a.; p = 0,016) em comparação aos controles no final da semana 7, quando a DMO foi mais proeminente. Uma forma grave de doença óssea de alta renovação celular acompanhou essas mudanças bioquímicas. A DO, medida na RxD foi correlacionada a P (r = -0,81; p = 0,002), ALP (r = -0,69, p = 0,01), PTH (r = -0,83, p = 0,01), OS/BS (r = -0,70 p = 0,02) e Ob.S/BS (r = -0,70; p = 0,02). Conclusão: A DO quantificada por RxD esteve associada às complicações típicas da DMO na DRC e mostrou-se viável na avaliação de alterações ósseas na DRC.
Asunto(s)
Animales , Masculino , Ratas , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/complicaciones , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/diagnóstico por imagen , Uremia/complicaciones , Intensificación de Imagen Radiográfica/métodos , Densidad Ósea , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico por imagen , Hormona Paratiroidea/sangre , Fosfatos/sangre , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/sangre , Uremia/inducido químicamente , Uremia/sangre , Adenina/efectos adversos , Biomarcadores/sangre , Remodelación Ósea , Ratas Wistar , Modelos Animales de Enfermedad , Fosfatasa Alcalina/sangre , Insuficiencia Renal Crónica/sangreRESUMEN
Supplementation of cyanate in rats caused a significant decrease in serum GSH and increase in calcium and phosphate level both in serum and lens. Consequently, these changes led to induce acidosis uremia in serum and hypercalcemia and hyperphosphatemia in lens which may be possible causing factor for cataract.
Asunto(s)
Acidosis/inducido químicamente , Animales , Calcio/metabolismo , Cianatos/toxicidad , Cristalino/efectos de los fármacos , Masculino , Fosfatos/metabolismo , Ratas , Uremia/inducido químicamenteRESUMEN
Long term maintenance of male rats of Long Evans variety following mercuric chloride induced uremia has shown an altered intramolecular structure of muscle glycogen with no significant difference in muscle glycogen content. The structure of muscle glycogen in these uremic rats when compared to sham control rats differed significantly from the structure of liver glycogen observed earlier in nephrectomized rats (Mannan et al., 1975). Biochemical analysis of muscle glycogen revealed a significant inverse relationship between the muscle and liver glycogen structure in terms of number of segments and number of non-reducing ends. Thus, an abnormal or altered muscle glycogen intramolecular structure of uremic rats is compatible with the observation of hypoglycemic state. Attributions of this to defects in glycogenolysis due to altered configuration in intramolecular structure of glycogen molecule are discussed.