Bone Abstracts

There is a growing body of evidence indicating the important role of the neonatal steroid milieu in programming sexually dimorphic pattern in various physiological systems. We tested the hypothesis that abnormal exposure to steroid hormones within a critical developmental period elicits permanent changes on tooth eruption, enamel mineralization, and leptin and corticosterone concentrations in adulthood. Newborn Wistar rats were divided into four groups, two male groups and two...

Osteoporosis is a multifactorial disease that represents an increase public health problem, given the impact on functional independence and quality of life. Among the favoring factors to the imbalance in bone cell activity, the hypoestrogenism is primordial. Strength training (ST) proves to be effective because of its ability to stimulate estrogen receptor independent of ligand. In this study, we analyzed the action of ST on bone quality of rats during the aging. For this stud...

To evaluate the regeneration of alveolar bone after treatment with bone-resorption inhibitors in old acyclic rats that had been through a long period of low estrogen. Thirty-two female Wistar rats with 20 months old intact and ovariectomized (OVX at 4 months of age), were randomized into four groups (n=8/group): i) intact; ii) OVX/O (corn oil); iii) OVX/E2 (17β-estradiol, 400 μg) and iv) OVX/RLX (Raloxifene, 1 mg/kg per day). All treatments began ...

The effects of neonatal thymectomy, at 3 days of age, on skeletal sexual dimorphism and bone quality during the development were examined in male and female Wistar rats. Rats were euthanized at 20, 40, or 120 postnatal days and femurs were collected. The Biomechanical compression test was used to evaluate bone breaking strength, energy-to-fracture, and extrinsic stiffness. During the prepubertal period, the neonatal thymectomy increases extrinsic stiffness of bone tissue signi...