RESUMO
PURPOSE: To test the possibility of obtaining a practical and stable model of hyperinsulinemia and hyperglycemia in hamsters, substituting the drinking water by 10% or 20% fructose solutions for a period of 2, 4, or 6 months. METHODS: Male hamsters were divided into 3 main groups, further divided in 3 subgroups: Two months: Group Ia control (n = 51) received filtered water, Group Ib (n = 49) received 10% fructose solution instead of water, Group Ic (n=8) received 20% fructose solution instead of water. Four months: Group IIa control (n=8), Group IIb 10% fructose (n = 7), Group IIc 20% fructose (FIIc, n = 7). Six months: Group IIIa control (n = 6), Group IIIb 10% Fructose (n = 6), Group IIIc 20% Fructose (n = 5). All groups were fed with the same laboratory diet. The animals were weighed every 2 weeks during the study period. On the final day of each experiment (61st, 121st, and 181st day after the beginning of the study, respectively), the animals were weighed and anesthetized for blood collection to determine plasma glucose and insulin after at least a 12-h fast. Ten animals of group Ia and 10 of group Ib were evaluated to determine changes in macromolecular permeability induced by ischemia/reperfusion as measured in the cheek pouch microcirculation. RESULTS: Compared to controls, the animals that drank the 10% or 20% fructose solution had significantly greater weight gain (P < .001), fasting plasma glucose (P < .001) Reperfusion, after 30 min ischemia, resulted in an immediate but reversible increase in postcapillary leakage (L) of 89.0 +/- 2.0 L/cm(2) (group Ia - controls), and 116.5 +/- 4.8 L/cm(2) (group Ib 10% fructose), P < .001. These results suggest that chronic administration of either 10% or 20% fructose solutions could be used to experimentally induce a stable hamster model of hyperinsulinemia and hyperglycemia. CONCLUSION: The model might facilitate the study of basic mechanisms of hyperglycemia and hyperinsulinemia affecting the microvasculature as demonstrated by the findings regarding ischemia/reperfusion after only 2 months of treatment.
Assuntos
Frutose/administração & dosagem , Hiperglicemia/induzido quimicamente , Hiperinsulinismo/induzido quimicamente , Animais , Peso Corporal , Cricetinae , Modelos Animais de Doenças , Masculino , Mesocricetus , Fatores de TempoRESUMO
PURPOSE: To test the possibility of obtaining a practical and stable model of hyperinsulinemia and hyperglycemia in hamsters, substituting the drinking water by 10 percent or 20 percent fructose solutions for a period of 2, 4, or 6 months. METHODS: Male hamsters were divided into 3 main groups, further divided in 3 subgroups: Two months: Group Ia control (n = 51) received filtered water, Group Ib (n = 49) received 10 percent fructose solution instead of water, Group Ic (n=8) received 20 percent fructose solution instead of water. Four months: Group IIa control (n=8), Group IIb 10 percent fructose (n = 7), Group IIc 20 percent fructose (FIIc, n = 7). Six months: Group IIIa control (n = 6), Group IIIb 10 percent Fructose (n = 6), Group IIIc 20 percent Fructose (n = 5). All groups were fed with the same laboratory diet. The animals were weighed every 2 weeks during the study period. On the final day of each experiment (61st, 121st, and 181st day after the beginning of the study, respectively), the animals were weighed and anesthetized for blood collection to determine plasma glucose and insulin after at least a 12-h fast. Ten animals of group Ia and 10 of group Ib were evaluated to determine changes in macromolecular permeability induced by ischemia/reperfusion as measured in the cheek pouch microcirculation. RESULTS: Compared to controls, the animals that drank the 10 percent or 20 percent fructose solution had significantly greater weight gain (P < .001), fasting plasma glucose (P < .001) Reperfusion, after 30 min ischemia, resulted in an immediate but reversible increase in postcapillary leakage (L) of 89.0 ± 2.0 L/cm² (group Ia - controls), and 116.5 ± 4.8 L/cm² (group Ib 10 percent fructose), P < .001.These results suggest that chronic administration of either 10 percent or 20 percent fructose solutions could be used to experimentally induce a stable hamster model of hyperinsulinemia and hyperglycemia. CONCLUSION: The model might facilitate...
OBJETIVO: Testar a possibilidade de obtenção de um modelo prático e estável de hiperinsulinemia e hiperglicemia em hamsters substituindo a água de beber por soluções de frutose a 10 por cento ou 20 por cento por um período de dois, quatro ou seis meses. MÉTODOS: Hamsters machos foram divididos em 3 grupos e cada grupo subdividido em 3 subgrupos. Dois meses: Grupo Ia-controle (n=51), recebeu água filtrada, Grupo Ib-(n=49), recebeu solução de frutose a 10 por cento ao invés de água e Grupo Ic-( n=8), recebeu solução de frutose a 20 por cento ao invés de água. Quatro meses: Grupo IIa - controle (n=8), Grupo IIb - 10 por cento frutose (n=7) e Grupo IIc - 20 por cento frutose (n=7). Seis meses: Grupo IIIa - controle (n=6), Grupo IIIb - 10 por cento frutose (n=6) e Grupo IIIc - 20 por cento frutose (n=5). Todos os animais foram alimentados com a mesma dieta padrão de laboratório. Os animais foram pesados a cada 2 semanas durante o período do estudo. No dia do final do experimento (61°, 121° e 181° dia, respectivamente, após o início do estudo), os animais foram pesados e anestesiados para coleta de sangue para determinação da glicose e da insulina sérica, após jejum de pelo menos 12 h. Em 10 animais do grupo Ia e em 10 do grupo Ib avaliamos, na microcirculação da bolsa da bochecha, a variação da permeabilidade a macromoléculas induzida por isquemia/reperfusão. RESULTADOS: Comparados ao grupo controle, os animais que beberam soluções de frutose a 10 ou 20 por cento tiveram um aumento significativo de massa corporal (p<0,001) e da glicemia de jejum (p<0,001). Durante o experimento de reperfusão, após 30 min de isquemia, houve um aumento imediato e reversível do extravasamento (E) pós-capilar de 89,0 ± 2,0 E/cm² (grupo Ia) e 116,5 ± 4,8 E/cm² (grupo Ib), p<0,001. CONCLUSÃO: Esse estudo sugere que a utilização crônica de solução de frutose a 10 por cento ou 20 por cento pode ser usada para induzir experimentalmente um modelo estável de hiperinsulinemia...