The effect of maternal hypercholesterolemia on the placenta and fetal arteries in rabbits / Efeito da hipercolesterolemia maternal sobre a placenta e as artérias fetais em coelhos

PURPOSE: To investigate the degree of placental permeability in dyslipidemic rabbits and the consequent vascular dysfunction in fetuses of female rabbits with high lipoprotein levels. METHODS: Fifteen adult females New Zealand White rabbits were divided into two groups. Group 1(n=5) - hypercholesterolemic diet with 0.5 percent cholesterol, and Group 2 (n=10) - control. On day 30, the levels of plasma lipoproteins and triglycerides were analyzed in the mothers, and the presence of collagen was analyzed in the placenta as well as in fetal coronary and aorta. Statistical analyses used the Student's t and the Mann-Whitney tests. RESULTS: Lipoprotein levels were significantly different (p=0.02 to p<0.001) in experimental and control groups. In the hypercholesterolemic group, total cholesterol levels were in average 793mg/dl; triglycerides were in average 257mg/dl; HDL-C was 48mg/dl, and LDL-C was in average 692mg/dl. The amount of collagen per micrometers square (mµ²) in samples from hypercholesterolemic animals was significantly higher than in the control group. CONCLUSIONS: The study confirmed placental permeability to lipoproteins, shown by increased amounts of collagen in fetal tissues. This alteration results in increased susceptibility to atherosclerosis in adult life, representing a risk factor for the early development of disease, which may appear even in the prenatal period.

OBJETIVO: Investigar a permeabilidade placentária em coelhos adultos fêmeas dislipidêmicas e a consequente disfunção vascular em seus fetos. MÉTODOS: Quinze coelhos adultos fêmeas Nova Zelândia Brancas foram distribuídas em grupo dislipidêmico e grupo controle. No trigésimo dia de gestação foram medidos os triglicerídeos e as lipoproteínas nas coelhas e verificada a presença de colágeno na placenta e coronárias fetais. Análise estatística foi feita com teste t de Student´s e Mann-Whitney. RESULTADOS: Os níveis de lipoproteínas foram diferentes estatisticamente entre os grupos (p=0,02 a p<0,001). A quantidade de colágeno por micrômetro quadrado foi significantemente maior no grupo hipercolesterolêmico em comparação ao grupo controle. CONCLUSÕES: O estudo confirmou a permeabilidade placentária para lipoproteínas demonstrando aumento de colágeno nos tecidos fetais. Esta alteração induz ao aumento da suscetibilidade para aterosclerose na vida adulta, representando um fator de risco para desenvolvimento precoce da doença aterosclerótica a qual pode estar presente mesmo no período pré-natal.

The effect of maternal hypercholesterolemia on the placenta and fetal arteries in rabbits.

PURPOSE: To investigate the degree of placental permeability in dyslipidemic rabbits and the consequent vascular dysfunction in fetuses of female rabbits with high lipoprotein levels. METHODS: Fifteen adult females New Zealand White rabbits were divided into two groups. Group 1(n=5) - hypercholesterolemic diet with 0.5% cholesterol, and Group 2 (n=10) - control. On day 30, the levels of plasma lipoproteins and triglycerides were analyzed in the mothers, and the presence of collagen was analyzed in the placenta as well as in fetal coronary and aorta. Statistical analyses used the Student's t and the Mann-Whitney tests. RESULTS: Lipoprotein levels were significantly different (p=0.02 to p<0.001) in experimental and control groups. In the hypercholesterolemic group, total cholesterol levels were in average 793 mg/dl; triglycerides were in average 257 mg/dl; HDL-C was 48 mg/dl, and LDL-C was in average 692 mg/dl. The amount of collagen per micrometers square (mµ²) in samples from hypercholesterolemic animals was significantly higher than in the control group. CONCLUSIONS: The study confirmed placental permeability to lipoproteins, shown by increased amounts of collagen in fetal tissues. This alteration results in increased susceptibility to atherosclerosis in adult life, representing a risk factor for the early development of disease, which may appear even in the prenatal period.

Ácido Láctico como indicativo de aptidão física em ratos / Lactic acid as an indication of physical fitness in rats

INTRODUÇÃO: Os modelos experimentais são utilizados para simulações de situações relacionadas ao treinamento físico. OBJETIVO: O objetivo do presente estudo foi verificar a aptidão física de ratos em treinamento através da avaliação das concentrações de ácido láctico sérico. METODOLOGIA: Foi realizado estudo experimental utilizando 40 ratos machos Wistar, adultos, divididos em cinco grupos de oito indivíduos, havendo um grupo controle. Foi realizado o primeiro teste de esforço máximo (TE) após uma semana de familiarização com a esteira rolante e antes do primeiro dia de treinamento. Os testes de esforço seguintes foram feitos a cada 10 dias de treinamento. No final de cada teste de esforço foi coletado 1ml de sangue para medir o ácido láctico. O teste t de Student foi utilizado para comparação das médias. RESULTADOS: O ácido láctico sérico diminuiu significativamente entre o primeiro e o último teste de esforço máximo nos grupos GE10, 20 e 30. No G30 pode-se demonstrar diferença significativa entre os testes inicial e final no que se refere à velocidade (p = 0,003) e tempo (p = 0,018), assim como no G40 velocidade inicial (p = 0,0006) e tempo (p = 0,0001). CONCLUSÃO: Os resultados demonstraram que ratos submetidos a treinamento físico apresentam capacidade metabólica medida pelo ácido láctico, que demonstra aptidão física e treinamento adequado com aumento do esforço físico, sendo bem tolerado até 40 dias de treinamento em esteira rolante.

INTRODUCTION: Experimental models are used for simulation of situations related to physical training. OBJECTIVE: This study had the objective of verifying the fitness of rats in training; this was achieved through the measurement of the concentration of lactic acid in the blood serum. METHODOLOGY: An experimental study using 40 Wistar male adult rats, divided into five groups of eight individuals and a control group was carried out. The first test of Maximum Effort (TE) was applied after one week of familiarization with the treadmill running and right before the first day of training. The following effort tests were applied at every ten days. In order to measure the concentration of lactic acid in the blood after the test; it 1ml of blood was collected from each rat. The Student t test was used to compare the means. RESULTS: Lactic acid serum significantly decreased in groups GE10, 20, 30 between the first and the last effort test. In the G30 there was a significant difference between the initial and final tests regarding speed (p = 0.003) and time (p = 0.018), as well as in the G40 group, where the initial velocity was (p = 0.0006) and time (p = 0.0001). CONCLUSION: The results measured through the lactic acid in the blood showed that rats submitted to physical training present better metabolic capacity and that with suitable training, the physical fitness increased after the physical effort. This effort is well tolerated by the rats up to 40 days of treadmill running.

Aleitamento materno exclusivo: análise desta prática na região sul do Brasil / Exclusive breastfeeding: analysis of practice in southern Brazil

Introdução: O ato do aleitamento materno representa a forma natural de alimentar uma criança nos primeiros meses de vida, sendo inquestionável o relevante papel que esta prática desempenha no crescimento e no desenvolvimento infantil. Os objetivos deste estudo foram: Estudar o tempo do aleitamento materno exclusivo em duas regiões do Rio Grande do Sul RS, estudar a associação entre o aleitamento materno e a escolaridade materna, trabalho materno e renda familiar. Metodologia: Estudo observacional, transversal e descritivo realizado em cinco idades do Rio Grande do Sul (Porto Alegre, Canoas, São Leopoldo, Caxias do Sul e Flores da Cunha). Para análise dos dados, com relação ao aleitamento materno exclusivo até os 6 meses, a amostra foi dividida em 2 grupos com 100 crianças, além da análise geral dessa variável. Esta divisão levou em consideração a localização de residência das mesmas. Resultados: Separando a amostra por regiões, verificou-se que na região serrana 60% das crianças receberam leite materno exclusivamente até os 6 meses de idade. Na região metropolitana, constatou-se que 30% receberam leite materno exclusivo até os 6 meses de idade. Conclusão: Constatamos que o aleitamento materno exclusivo até os 6 meses foi o dobro na região da serra riograndense, em comparação com a região metropolitana.

Introduction: Breastfeeding is the natural way of feeding a child in the first months of life, and the relevant role played by this practice in child growth and development is undisputed. The aims of this study were to study the length of exclusive breastfeeding in two regions of Rio Grande do Sul (RS), and to assess the association of maternal breastfeeding with mother schooling, maternal employment, and family income. Methods: Observational, cross-sectional descriptive study performed in 5 cities of RS (Porto Alegre, Canoas, São Leopoldo, Caxias do Sul and Flores da Cunha). For data analysis, regarding exclusive maternal breastfeeding until 6 months, the sample was divided in two groups with 100 children, besides the general analysis of this variable. Results: By analyzing the sample by region, we found that 60% of the infants in the countryside (Caxias do Sul and Flores da Cunha) were exclusively breastfed until 6 months of age. In the metropolitan region (Porto Alegre, Canoas, São Leopoldo), this proportion was 30%. Conclusion: We found that exclusive breastfeeding until 6 months of age in the “Região Serrana” was twice as common as in the metropolitan region

Comparison of rimonabant and sibutramine treatment effects on food compulsion in rats.

PURPOSE: To compare the therapeutic effect of rimonabant, a new drug which is a selective antagonist of CB1 receptors, with the sibutramine. METHODS: It is an experimental clinical trial, prospective, placebo controlled. Our test was performed in 38 rats, adults females with a hyper caloric diet. We collected their blood 3 times and weighted them once a week. We divided the rats in 3 groups: Rimonabant, Sibutramine and Control. Statistic analysis has been made through ANOVA test, Tukey test and t Student test. RESULTS: The Rimonabant group demonstrated a significant reduction of the weight increase in rats. The Sibutramine group showed a significant reduction on blood glycemia compared to Rimonabant group and Control group. CONCLUSIONS: Rimonabant showed to be more effective than Sibutramine by decreasing weight gain. Sibutramine has been more effective than Rimonabant and Control groups by decreasing the blood glycemia.

Comparison of rimonabant and sibutramine treatment effects on food compulsion in rats / Comparação do efeito do rimonabanto e da sibutramina no tratamento da compulsão alimentar em ratos

PURPOSE: To compare the therapeutic effect of rimonabant, a new drug which is a selective antagonist of CB1 receptors, with the sibutramine. METHODS: It is an experimental clinical trial, prospective, placebo controlled. Our test was performed in 38 rats, adults females with a hyper caloric diet. We collected their blood 3 times and weighted them once a week. We divided the rats in 3 groups: Rimonabant, Sibutramine and Control. Statistic analysis has been made through ANOVA test, Tukey test and t Student test. RESULTS: The Rimonabant group demonstrated a significant reduction of the weight increase in rats. The Sibutramine group showed a significant reduction on blood glycemia compared to Rimonabant group and Control group. CONCLUSIONS: Rimonabant showed to be more effective than Sibutramine by decreasing weight gain. Sibutramine has been more effective than Rimonabant and Control groups by decreasing the blood glycemia.

OBJETIVO: Comparar o efeito do rimonabanto, nova droga seletivamente antagonista dos receptores CB1, com a sibutramina. MÉTODOS: Ensaio clínico experimental, prospectivo, placebo controlado. Realizado com 38 ratas, adultas, submetidas a dieta hipercalórica. Foram coletadas 3 amostras de sangue e o peso controlado semanalmente. Foram divididas em 3 grupos: Rimonabanto, Sibutramina e Controle. Analise estatística realizada com ANOVA, teste t de Student e teste de Tukey. RESULTADOS: O grupo Rimonabanto obteve redução significante do ganho de peso. O grupo Sibutramina teve redução significativa da glicemia quando comparado aos demais grupos. CONCLUSÕES: Rimonabanto foi mais efetivo que a Sibutramina na redução do ganho de peso. A Sibutramina foi mais efetiva na redução da glicemia do que os grupos controle e Rimonabanto.