In considering thyroid hormone regulation and homeostasis, it is important to examine some characteristics of this hormone in relation to the others. The hor­ mones may readily be divided into two distinct physicochemical and biological classes. (Table 1). The protein and peptide hormones are water soluble and evidently exist in the plasma without demonstrable interaction with other serum prote...

INTRODUCTION Previous studies have shown that hormonal factors such as levels of insulin, cortisol, testosterone, and insulin resistance are related with increased nephrolithiasis (NL). However, no previous study has evaluated the relationship between insulin, insulin resistance, thyroid hormones, cortisol, intact parathyroid hormone and testosterone levels with the presence of NL in a comprehe...

Parathyroid carcinoma is very rare, with only a few documented cases. Hence, metastatic lesions are infrequently documented on scintigraphic imaging. We present a case of a 63-year-old female presenting with elevated serum levels of ionized calcium and parathyroid hormone (PTH) who was referred to our department for a parathyroid scan with SPECT/ CT. Parathyroid scintigraphy showed a focus of i...

Thirty one patients with biologic and clinical diagnosis of hyperparathyroidism were submitted to thalium-technetium scan prior to exploration of the neck. Scan findings were compared with the pathologic results. Surgical exploration of the neck showed a parathyroid adenoma in 24 patients, parathyroid carcinoma in one patient, normal parathyroid in another patient and parathyroid hyperplasia in...

Dr. Mehmet Şükrü Sever Ataköy, 4. Kisim, TO Blok No: 216, D:15 Bakirköy İstanbul (Turkey) Dear Sir, The kidneys (together with the liver) are responsible for most of the metabolism of polypeptide hormones; furthermore some hormones such as calcitonin (CT) and the N-terminal fragment of parathyroid hormone (PTH) are not metabolized by the liver, hence the role of the kidneys becomes more importa...

CALCIUM Calcium ion plays a key role in many fundamental biologic processes including muscle contraction, blood coagulation, enzyme activity, neural excitability, hormone release, and membrane permeability, in addition to being an essential structural component of the skeleton. Therefore, the precise control of calcium ion in extracellular fluids is vital to the health of humans and animals. To...

Most dairy cows experience some degree of hypocalcemia during the periparturient period. There is, however, a sub-group of dairy cows that experience a breakdown in their ability to maintain plasma calcium and, consequently, suffer from severe hypocalcemia. This condition is also known as milk fever and usually occurs in cows in their third or greater lactation. The precise metabolic lesions re...

This review summarizes research on sensory and behavioral aspects of calcium homeostasis. These are fragmented fields, with essentially independent lines of research involving gustatory electrophysiology in amphibians, ethological studies in wild birds, nutritional studies in poultry, and experimental behavioral studies focused primarily on characterizing the specificity of the appetite in rats...

IN THE LAST YEARS THERE HAS BEEN AN INCREASED AWARENESS REGARDING THE ALTERATIONS OF BONE METABOLISM AS A COMMON COMPLICATION OF CHRONIC LIVER THAT OCCURS REGARDLESS OF THE ETIOLOGY: alcoholic, viral, autoimmune, whether or not associated with cholestasis.The aim of this paper was to summarize the current understanding of bone metabolism and to point out the new discoveries that have been made ...

The pituitary gland has come to be regarded as the master key of the endocrine system in so far as it influences the activity of the remaining glands, but a reciprocal influence in the opposite direction is equally important. Hypophysectomy results in diminished function and some degree of. atrophy in the gonads, adrenals, thyroid, pancreas, and less certainly of the parathyroids; and conversel...