Apoptosis, proliferation and histomorphometry of spleen were investigated in ovariectomized and non-ovariectomized adult Wistar rats maintained in hypothyroidism induced by daily administration of propylthiouracil (PTU) during 120 days. Two groups ovariectomized euthyroid and non-ovariectomized euthyroid were used as controls. Plasma was collected for free T4 dosage and the spleen for histomorphometry analysis, apoptosis index and the immunohistochemistry expression of caspase 3 and CDC47. Values of free T4 were lower in rats treated with PTU (p<0.05). In the hypothyroid groups there […]

The objective of this study was to verify if hyperthyroidism potentiates the osteopenia lactational. 24 adult female rats were distributed in four groups: euthyroid no lactating (control), euthyroid lactating, hyperthyroid no lactating and hyperthyroid lactating. 20 days after gestation, all the animals were necropsied. The thoracic and lumbar vertebrae, the femur and tibia were decalcified and processed for histomorphometric analysis. The euthyroid lactating group presented intense osteopenia in the studied bones. In the hyperthyroid no lactating group, there was not […]

Osteoclastogenesis may be regulated via activation of the RANK/RANKL (receptor activator of nuclear factor-kappa B/ receptor activator of nuclear factor-kappa B ligand) system, which is mediated by osteoblasts. However, the bone loss mechanism induced by T3 (triiodothyronine) is still controversial. In this study, osteoblastic lineage rat cells (ROS 17/2.8) were treated with T3 (10-8 M, 10-9 M, and 10-10 M), and RANKL mRNA (messenger RNA) expression was measured by semiquantitative RT-PCR. Our results show that T3 concentrations used did not […]

The purpose of this study was to evaluate mammary gland histomorphometry and proliferation rate and apoptosis of thyroxine-treated rats by CDC-47 and caspase-3 immunoexpression. The development of thyroxine-treated rats offspring was also evaluated. Thirty-six female rats were used, distributed in two groups, treated and non-treated with thyroxine. After 60 days of treatment, with thyroxine, rats were mated. Six animals/group were sacrificed on the 2nd and 21st days of lactation and on the 5th day after weaning. A significant difference was […]

The relationship between thyroid, gonads and bone morphology was investigated in 5 month-old Wistar rats, castrated and kept in hyperthyroid or euthyroid state for periods of 30, 60 and 90 days. A non-castrated control group was maintained in the same condition. At the end of each period, plasma concentrations of free T4, progesterone and estradiol were measured. The bones from each group were submitted to radiological and histological analysis. Hyperthyroidism in intact rats caused variation in bone morphology throughout the […]

The effect of hypothyroidism on bone metabolism and the parathyroids in states of deficiency or sufficiency of sex steroids was studied in 32 two-months-old female Wistar rats distributed in 4 groups of 8 animals each: intact euthyroid (IE), castrated euthyroid (CE), intact hypothyroid (IH) and castrated hypothyroid (CH). After 120 days of treatment, animals were sacrificed and plasma taken to assess free T4. Hyperplasia or hypertrophy of all parathyroids were evident only in IH and CE groups. Of all groups, […]

The relationship between thyroid-gonads on the blood profile was investigated in adult Wistar female rats. These animals were either castrated or intact and were kept under hypothyroidism, induced by daily administration of propylthiouracil (PTU) during 120 days. Two groups (castrated and intact) were kept in an euthyroid condition and used as controls. It was collected plasma for free T4 dosage and blood for hematological analysis. The significant low values of free T4 in the treated rats confirmed their hypothyroid state. […]