Background: Thyroid hormone has been shown to control retinal cone opsin expression, the protein of color vision, in adult rodents. Objectives: The aim of this study was to evaluate the effect of hypothyroidism on color contrast sensitivity in adult overt hypothyroid patients. Methods: Thirtyeight overt hypothyroid (31 females, 7 males) subjects and 20 euthyroid (16 females, 4 males) controls w...

BACKGROUND Ischemic postconditioning (IPost) is a method of protecting the heart against ischemia-reperfusion (IR) injury. However, the effectiveness of IPost in cases of ischemic heart disease accompanied by co-morbidities such as hypothyroidism remains unclear. OBJECTIVE The aim of this study was to determine the effect of IPost on myocardial IR injury in hypothyroid male rats. METHODS Pr...

It has been suggested that hypothyroidism may alter the responsiveness of the heart to sympathetic stimulation. To define more precisely the interrelationship between hypothyroidism and catecholamine responsiveness we: (a) studied the effects of norepinephrine and fluoride on the activation of adenyl cyclase in the particulate fraction of heart homogenates from euthyroid and hypothyroid cats; a...

Objective To investigate the cardiometabolic effects of a severe hypothyroid state induced by withdrawal of thyroid hormone replacement before radioactive iodine therapy. Methods Patients with thyroid cancer who were scheduled to receive radioactive iodine ablation were enrolled. Cardiometabolic parameters were measured using blood samples taken immediately before levothyroxine withdrawal, 4 we...

Objectives – To find the effect Of TSH suppression therapy on levels of TSH, T4 and T3 in hypothyroidism. Methods The study comprised of 40 subjects, classified into 2 groups each, with 20 subjects. Group I – 20 (Healthy individuals) controls aged between 20 – 45 years with euthyroid status. Group II20 Hypothyroid subjects with suppressed levels of TSH aged between 20 to 45 years. The parameter...

Hepatocytes from hypothyroid rats respire more slowly than those from control animals; cells from hyperthyroid rats respire faster. We have identified the blocks of reactions whose kinetics are significantly affected by thyroid hormones and have quantified the contribution of flux through different blocks of energy-dissipating reactions to the altered oxygen consumption. In cells from hypothyro...

Free radical-mediated oxidative stress has been implicated in the etiopathogenesis of several autoimmune disorders. Hypothyroidism in humans is widely believed to impair health. The biochemical factors mediating decline in health, however, are poorly elucidated. Pathological consequences of hypothyroidism point to a high potential for antioxidant imbalance. The study population consisted of 60 ...

The diagnosis of canine hypothyroidism and its differentiation from euthyroid sick syndrome still is a major diagnostic challenge. In this study, ultrasonography was shown to be an effective tool for the investigation of thyroid gland diseases. Healthy control dogs (n = 87), dogs with euthyroid sick syndrome (n = 26), thyroglobulin autoantibody-positive (TgAA-positive, n = 30) hypothyroid dogs,...

The initial rate of lecithin: cholesterol acyl transferase and serum concentration of lipids were determined in euthyroid, hypothyroid and hyperthyroid subjects. In hyperthyroid subjects, the serum levels of total and free cholesterol were significantly lower than in normal subjects and the fractional lecithin: cholesterol acyl transfer rate was significantly higher than in normal subjects. The...

Thyroid hormone is known to exert important effects on cardiac repolarization, but the underlying mechanisms are poorly understood. We investigated the electrophysiological mechanisms of differences in repolarization between control guinea pigs and hypothyroid animals (thyroidectomy plus 5-propyl-2-thiouracil). Hypothyroidism significantly prolonged the rate-corrected Q-T interval in vivo and a...