introduction: thyroid hormones play an important role in the regulation of metabolism, maturity and reproduction. thyroid dysfunction affects almost all endocrine glands such as pituitary and testis. the aim of this study was to investigate alterations of testosterone and luteinizing hormone (lh) serum levels as well as weights of thyroid gland and testes in methimazole (mmi)-induced hypothyroi...

  Objective(s): Previous studies have shown that thyroid hormones are necessary for normal development of many organs and because of the importance of skin as the largest and the most important organ in human body protection in spite of external environment, the study of thyroid hormones effects on skin development is considerable. In this survey we have tried to study the effects of maternal h...

Thyroid hormones, previously thought not to affect spermatogenesis and male fertility, are now being recognized as having important role in spermatogenesis. The identification of thyroid hormone receptors on Sertoli cells, the nurturing cells for sperm in the testis, has embarked further research to investigate the role of thyroid hormones in male reproduction. Since spermatogenesis occurs in c...

The importance of thyroid hormones during brain development has been appreciated for many decades. In humans, low levels of circulating maternal thyroid hormones, e.g., caused by maternal hypothyroidism or lack of iodine in diet, results in a wide spectrum of severe neurological defects, including neurological cretinism characterized by profound neurologic impairment and mental retardation, und...

Ghrelin increases food intakes and body weight. Bombesin decreases food intakes and inhibits the stimulatory effect of Ghrelin on food intakes. Thyroid hormones have a crucial role in the regulation of body weight and yet the effect of bombesin on thyroid axis activity is not fully clear. Therefore, the goal of this study was to determine the effect of different doses of Ghrelin or bombesin on ...

Background and aim: Melasma is an acquired, symmetric hyperpigmentation, specially in sun-exposed skin. Disorders of thyroid gland result from processes that stimulate the overproduction or underproduction of thyroid hormones. This study was performed to assess the association of melasma with thyroid disorders.Materials and Methods: This case-control study was performed...

Thyroid hormones are essential for normal brain development, growth and energy metabolism [1]. During early pregnancy, the foetus is entirely dependent on maternal thyroid hormones and in the second and third trimesters, maternal thyroid hormones continue to provide sufficient thyroid hormones until birth [2,3]. Maternal thyroid disease is common during pregnancy with hyperthyroidism during pre...

Three hormones, thyroxine (3,5,3 ,5 -tetraiodothyronine, or T4), triiodothyronine (3,5,3 -triiodothyronine, or T3), and calcitonin (see Chapter 66) are secreted by the thyroid gland. The hormones T4 and T3 are iodinecontaining amino acid derivatives and are unique in that they have no discrete target tissue. Every tissue in the body is affected in some way by thyroid hormones, and almost all ce...

Leydig cells are the primary source of androgens in the mammalian testis. It is established that the luteinizing hormone (LH) produced by the anterior pituitary is required to maintain the structure and function of the Leydig cells in the postnatal testis. Until recent years, a role by the thyroid hormones on Leydig cells was not documented. It is evident now that thyroid hormones perform many ...