Right ventricular papillary muscles from hyperthyroid and normal cats were studied in vitro at 30°C, at contraction frequencies of 12, 30 and 60/min. At 12/min the contractility of hyperthyroid muscles was significantly greater than normal, as indicated by greater velocity of isotonic shortening, isometric tension development, and rate of tension development. Isotonically contracted muscle leng...

We previously reported that serum interleukin-12 (IL-12) levels were significantly increased in patients with hyperthyroid Graves' disease and in normal subjects after administration of thyroid hormone. In the present study, we investigated which cells produce IL-12 and the interactions between IL-12 and thyroid hormones, using a hyperthyroid mouse model. Thyroid hormones induced IL-12 producti...

BACKGROUND Atrial fibrillation (AF) is the most common arrhythmia in adults, and is encountered in 10-15% of the patients with hyperthyroidism. Unless euthyroidism is restored, pharmacological or electrical cardioversion is controversial in patients with AF who remain hyperthyroid. OBJECTIVE The aim of this study was to assess the efficacy of electrical cardioversion and predictors of AF recu...

BACKGROUND The contribution of fat loss versus muscle wasting to the loss of body weight seen in hyperthyroid cats is unknown. OBJECTIVES To investigate body weight, body condition score (BCS), and muscle condition score (MCS) in hyperthyroid cats. ANIMALS Four hundred sixty-two cats with untreated hyperthyroidism, 117 of which were reevaluated after treatment. METHODS Prospective cross-s...

Maximum left ventricular systolic pressure response to aortic constriction served as a measure of myocardial contractility in anesthetized euthyroid and hyperthyroid guinea pigs. This response in hyperthyroid guinea pigs (155.4 ± 1.40 mm Hg) was significantly greater than in euthyroid animals (147.3 ± 1.33 mm Hg) (P<.001) and developed at a lower end-diastolic pressure in hyperthyroid (11.27 ±0...

SUMMARY Although the circulatory changes in various thyroid states are well known, the alterations of myocardial contractility of hypothyroidism and hyperthyroidism have remained controversial. The changes in the length of the ejection time (ET) and isovolumic contraction time (ICT) are used as indicative of alterations in inotropic state of the myocardium. Isovolumic contraction time, ejection...

introduction: some studies indicate changes in the level of thyroid hormones in addicted people. also, there are some reports concerning the modulation of hypothalamus-hypophysis-thyroid axis in the context of morphine addiction. in the present study, the effects of thyroid gland activation via the acute and chronic administration of levothyroxine on morphine withdrawal syndrome were investigat...

Measurements of the frequency-force relationship were made in left atrial muscle from euthyroid and hyperthyroid guinea pigs and the effects of calcium and norepinephrine on this relationship examined. Isometric contractile force was measured with the muscle suspended in a bath of Krebs-Henseleit solution oxygenated by a gas mixture of 95£ O2-5% CO2 at 28°C. Frequency of stimulation was varied ...

INTRODUCTION Hyperhomocysteinaemia is an independent risk factor for premature atherosclerotic vascular disease and venous thrombosis. Hypothyroidism is associated with mild hyperhomocysteinaemia. The aim of the present study was to assess plasma total homocysteine (tHcy) and its determinants (folate, cobalamin) in hyperthyroid patients before and after treatment. MATERIAL AND METHODS Thirty ...