Prolonged thyroid-stimulating hormone (TSH) suppression caused by exogenous subclinical thyrotoxicosis has been reported to impose harmful effects on cardiovascular system. Those effects involve increase in heart rate and myocardial mass, impaired ventricular diastolic and systolic function, decreased exercise capacity, decreased arterial elasticity, development of atrial tachyarrhythmia, and increase in cardiovascular adverse events. Tailored dose adjustment of thyroid hormone under the guidance of TSH level for obviating oversuppression of TSH, and use of beta blockers can reduce cardiovascular adverse effects in patients who undergo thyroid hormone therapy.
Cardiovascular System ; Elasticity ; Heart Rate ; Humans ; Tachycardia ; Thyroid Gland ; Thyrotoxicosis ; Thyrotrophs ; Thyrotropin

This study was performed to investigate the effect of Matrigel, a reconstituted basement membrane, on the expression of the anterior pituitary hormones in culture. Rat pituitary cells cultured for 6 days on Matrigel showed 3-dimensional, lobular structures with connecting cells while those on plastic showed flat, polygonal cells forming a monolayer. Western blot analysis showed that prolactin (PRL) content in the anterior pituitary cells was higher compared to those cultured on plastic. In comparison, TSH expression was not increased in cultures on Matrigel. The total cell number and the proportion of fibroblasts was decreased. These results suggested that Matrigel is a useful culture substrate for the enhanced expression of PRL but not for TSH. Further studies are needed in order to find a useful culture substrate for TSH cells.
Animals ; Basement Membrane* ; Blotting, Western ; Cell Count ; Fibroblasts ; Pituitary Hormones, Anterior* ; Plastics ; Prolactin ; Rats* ; Thyrotrophs

Conflicting results have been reported, as to whether or not wound repair is influenced following treatment with low doses of prednisolone, insulin, or thyrotrophic hormone. The present studies were undertaken to evaluate and compare the influence of above hormones on the wound repair process and their target organs in rats at different times after operation. The influence of the above hormones were observed as measurement of the tensile strength of healing skin incisions and the histologic finding of the wound sites and the target organs staining with H-E, PAS, and Masson's trichrome method. Saline 0. 1 ml were injected daily intramusculary in control group: prednisolone acetate 0. 2ml (4mg/kg/day) in prednisolone treated group: regular zinc insulin 0.1 ml(1.5IU/kg/day) in insulin treated group; thyrotrophin 0.1 ml (0.4IU/kg/day) in TSH trcated group. The observation period wer at 4th day, 7th day, 14th day and 21st day of post-operation. The results were as follows: 1. Prednisolone treated group: (1) The tensile strength were decreased at 4th and 7th day than control groups, but there were no statistically significant difference at 14th and 21st day from control group. (2) In histologic findings of the wound sites at 4th and 7th day, the repair processes were suppressed, but at 14th and 21st day, there were no difference from control group. (3) In histologic finding of adrenal cortex, the atrophic changes was observed from early stage. 2. Insulin treated group: (1) There were no statistical difference from control group in tensile strength at each observation period. (2) In histologic findings of the wound sites, the pictures of the repair processes were similar with control group at each observation period. (3) Atrophic change of islets of Langerhans in pancreas was observed at each observation period. 3. TSH treated group: (1) The tensile strength were increased at 4th, 7th, and 14th day than control group, but there was no statistical difference at 21st day frorn control group. (2) In histologic findings of the wound sites, the repair processes were aecelerated at 4th and 7th day than control group, but there were no defferences at 14th and 21st day from control group. (3) Hyperplastic change of acini in thyroid gland was observed through entire observation period.
Adrenal Cortex ; Animals ; Insulin ; Islets of Langerhans ; Pancreas ; Prednisolone ; Rats ; Skin ; Tensile Strength ; Thyroid Gland ; Thyrotrophs ; Thyrotropin ; Wounds and Injuries* ; Zinc

Thyroid hormone (TH) has a pivotal role in skeletal development, linear growth and maintenance of adult bone mass. Additionally, there are several studies which supported the direct effect of thyroid-stimulating hormone (TSH) on bone metabolism. As thyroid disease is one of the most common endocrine problems, the clinical impact of thyroid dysfunction on bone metabolism has been elucidated in various studies. Hyperthyroidism is associated with excessive loss of bone mass and an increased life-time risk for fractures. Adverse effects of hyperthyroidism in bone metabolism are distinct in postmenopausal women. Subclinical hyperthyroidism may also affect bone mineral density, however, its effect on fracture rate remains to be established. The effect of exogenous TH on bone tissue is somewhat controversial. Patients with hypothyroidism or differentiated thyroid carcinoma showing suppressed TSH caused by excessive TH replacement, especially postmenopausal women, appear to have lower bone mineral density and higher incidence of fractures than euthyroid subjects without exogenous TH. On the contrary, patients who are on exogenous TH with a normal range of TSH seem to have similar bone mineral density and fracture rates as euthyroid subjects. As most patients with differentiated thyroid carcinoma are taking exogenous thyroid hormone to suppress TSH, individual risks of both fracture and recurrence of carcinoma should be evaluated during the follow-up period of those patients. In general, in the management of thyroid disease, it should be taken into account that most thyroid dysfunction may result in reduced bone density and an increased fracture rate.
Adult ; Bone and Bones ; Bone Density ; Female ; Follow-Up Studies ; Humans ; Hyperthyroidism ; Hypothyroidism ; Incidence ; Recurrence ; Reference Values ; Thyroid Diseases ; Thyroid Gland ; Thyroid Neoplasms ; Thyrotrophs ; Thyrotropin

Growth hormone (GH) and thyrotropin (TSH)-secreting pituitary adenomas are very rare and account for only 0.5% of all pituitary adenomas. We report a case of a GH/TSH-secreting pituitary adenoma in a 53-year-old male patient. He presented with symptoms of thyrotoxicosis, clinical features of acromegaly, and diabetes mellitus. The laboratory examinations showed high serum levels of free T4, TSH, and free alpha-subunit. Additionally, serum levels of GH and insulin-like growth factor (IGF-1) wereincreased. GH was not suppressed below 1 microgram/L by an oral 75 g glucose loading test, and TSH was not stimulated by thyrotropin- releasing hormone. A sellar MRI showed a large lobulated mass on the pituitary gland, so transcranial surgery was performed. Immunohistochemical staining showed anti-GH and anti-TSH positive tumor cells in the cytoplasm. Serum GH, IGF-1, free T4, and TSH levels normalized after surgery.
Acromegaly ; Cytoplasm ; Diabetes Mellitus ; Glucose ; Growth Hormone ; Humans ; Insulin-Like Growth Factor I ; Male ; Middle Aged ; Pituitary Gland ; Pituitary Neoplasms ; Thyrotoxicosis ; Thyrotrophs ; Thyrotropin