Evaluation of anaerobic threshold in non-pregnant and pregnant rats

ABSTRACT Several studies present different methodologies and results about intensity exercise, and many of them are performed in male rats. However, the impact of different type, intensity, frequency and duration of exercise on female rats needs more investigation. From the analysis of blood lactate concentration during lactate minimum test (LacMin) in the swimming exercise, the anaerobic threshold (AT) was identified, which parameter is defined as the transition point between aerobic and anaerobic metabolism. LacMin test is considered a good indicator of aerobic conditioning and has been used in prescription of training in different exercise modalities. However, there is no evidence of LacMin test in female rats. The objective was to determine AT in non-pregnant and pregnant Wistar rats. The LacMin test was performed and AT defined for mild exercise intensity was from a load equivalent to 1% of body weight (bw), moderate exercise as carrying 4% bw and severe intensity as carrying 7% bw. In pregnant rats, the AT was reached at a lower loading from 5.0% to 5.5% bw, while in non-pregnant the load was from 5.5% to 6.0% bw. Thus, this study was effective to identify exercise intensities in pregnant and non-pregnant rats using anaerobic threshold by LacMin test.

Effect of Bauhinia holophylla treatment in Streptozotocin-induced diabetic rats

ABSTRACT Bauhinia holophylla, commonly known as "cow's hoof", is widely used in Brazilian folk medicine for the diabetes treatment. Therefore, the aim of this study was at evaluating the aqueous extract effect of Bauhinia holophylla leaves treatment on the streptozotocin-induced diabetic rats. Diabetes was induced by Streptozotocin (40 mg/Kg) in female Wistar rats. Oral administration of aqueous extract of Bauhinia holophylla leaves was given to non-diabetic and diabetic rats at a dose of 400 mg/kg during 21 days. On day 17 of treatment, the Oral Glucose Tolerance Test was performed to determine the area under the curve. At the end of the treatment, the animals were anesthetized and blood was collected for serum biochemical parameters analysis. After treatment with Bauhinia holophylla extract, non-diabetic and diabetic rats presented no glycemic changes. On the other hand, the plant treatment decreased body weight and increased ALT and AST activities. In conclusion, the treatment with aqueous extract of B. holophylla leaves given to diabetic rats presented no hypoglycemic effect in nondiabetic animals and no antidiabetic effect in diabetic animals with the doses studied. In addition, the diabetic animals treated with the B. holophylla extract showed inconvenient effects and its indiscriminate consumption requires particular carefulness.

Comparative analysis of two different models of swimming applied to pregnant rats born small for pregnant age

ABSTRACT The aim of this study was to compare two models of swimming applied to pregnant rats born small for pregnancy age (SPA). Diabetes was chemically induced in adult female rats to develop an inadequate intrauterine environment, leading to birth of a SPA offspring. In adulthood, the female SPA rats were mated and submitted to different swimming programs. The exercise program 1 (Ex1) consisted of swimming for 15 minutes, followed by 15 minutes of rest and another 15 minutes of swimming, 3 days a week before and during pregnancy. Another program (Ex2) was applied during 60 minutes uninterrupted a day, 6 days/week during pregnancy. The pregnant rats presented no interference on body weight and glycemia. The rats submitted to Ex2 model showed decreased insulin and blood glucose levels by oral glucose tolerance test, and reduction in area under curve values. The offspring from dams submitted to both exercise protocols presented an increased rate of newborns SPA. However, the offspring from Ex2 dams showed percentage twice higher of newborns SPA than Ex1 offspring. Our data suggests that continuous exercise of 60 min/day ameliorated the enhanced peripheral insulin sensitivity in growth-restricted females. However, this protocol employed at pregnancy leads to intrauterine growth restriction.

Estudos dos extratos de folhas de Averrhoa carambola e eugenia jambolana, obtidas em farmácia de manipulaçäo, sobre o diabete experimental / Study

O objetivo deste trabalho foi investigar se os extratos das folhas de jamboläo (Eugenia jambolana) e de carambola (Averrhoa carambola), comercializados em larga escala por farmácias de manipulaçäo, realmente apresentam afeito hipoglicemiante quando testados em ratas com diabete induzido por streptozotocin. Cada extrato foi preparado com as folhas secas de jamboläo e de carambola por decocçäo (5g/1000mL), de forma semelhante ao método de preparaçäo recomendado à populaçäo. Entretanto, as doses utilizadas foram seis vêzes maiores que a consumida popularmente. Foram utilizadas ratas Wistar divididas aleatoriamente em 3 grupos: diabéticas-controle que receberam água destilada (C,n=7), diabéticas tratadas com 105,0mg/kg do extrato aquoso de carambola (DTC, n=7) e com 50,0mg/kg do extrato de jamboläo (DTJ,n=7), via oral (gavage)