Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

TSH serum levels and thyroid function in 32 patients with primary hyperparathyroidism and hypercalcemia were compared to those of 30 age and sex-matched normal subjects. Serum T3 and T4 concentrations in hyperparathyroidism were not different from normal. However, basal serum TSH concentrations measured with an ultrasensitive immunoradiometric assay were significantly lower than normal (1.09 +/- 0.49 vs 2.06 +/- 0.85 mU/l, p less than 0.001). In hyperparathyroidism, TSH, but not T4 or T3, was negatively correlated with serum calcium, not with iPTH. The increase in TSH (delta TSH) 30 min after the iv injection of TRH was also significantly blunted in patients with primary hyperparathyroidism; delta TSH was highly correlated with basal TSH in hypercalcemic patients. The basal TSH concentration was higher and no longer different from normal (1.70 +/- 1.2 mU/l) 2 to 12 months after removal of the parathyroid adenoma, when serum calcium was normalized, whereas T3 and T4 did not change. A low basal TSH with normal T4 and low T3 was found in 13 patients with hypercalcemia of malignancy. In these patients, TSH increased after treatment of hypercalcemia with 3-amino-l,hydroxypropylidene-1, 1-bisphosphonate, whereas T4 did not change. The results suggest that the set point of pituitary thyroid feedback control could be decreased in chronic hypercalcemia and that hypercalcemia could render the thyroid more sensitive to TSH.
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PMID:Low basal thyrotropin with normal thyroid function in primary hyperparathyroidism. 251 13

Multiple endocrine neoplastic diseases are genetically determined conditions with particular organ patterns for endocrine tumors. In Type I or Wermer's syndrome the endocrine pancreas, anterior pituitary and parathyroids are involved, insulinoma being the most frequent pancreatic tumor. To facilitate diagnosis, a prolonged oral glucose tolerance test, a fasting test and determination of the glucose-insulin ratio are recommended. Localisation is sought by computer tomography and angiography. A gastrinoma is excluded on the basis of normal gastrin levels in serum and by means of the secretin-provocation-test. Pituitary tumors can be classified more closely with prolactin levels and releasing-hormone tests (LH-RH and TRH). Prolactinoma is the most frequent pituitary tumor and amenable to bromocryptin treatment. If Wermer's syndrome is suspected, primary hyperparathyroidism has to be excluded on the basis of calcium and parathormone levels. Chief cell hyperplasia or multiple adenomas are frequent. Surgical resection is necessary.
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PMID:[Type I multiple endocrine neoplasia--Wermer syndrome]. 257 44

The influence of changes in the serum calcium concentration on TSH secretion was evaluated in patients with primary hyperparathyroidism and idiopathic hypoparathyroidism and in normal subjects. Serum calcium concentrations were 12.7 +/- 0.8, 9.0 +/- 0.4, and 5.7 +/- 0.5 mg/100 ml in hyperparathyroid, normal, and hypoparathyroid subjects, respectively, and were significantly different from each other. Serum T3 and T4 concentrations were comparable among the three groups. The basal serum TSH concentration was highest in hypoparathyroid, lowest in hyperparathyroid, and intermediate in normal subjects. However, all values were within normal limits and were not significantly different from each other. TRH-stimulated TSH secretion was significantly greater in hypoparathyroid patients and significantly less in hyperparathyroid patients than in normal subjects, respectively. The TSH response to TRH was normalized when the serum calcium concentration was normalized by parathyroidectomy in a hyperparathyroid patient or by 1 alpha-hydroxyvitamin D3 administration in a hypoparathyroid patient. To further clarify the mechanism responsible for the modified TSH response to TRH in the hypercalcemic state, rats were made chronically hypercalcemic by the administration of 1 alpha-hydroxyvitamin D3 (0.2 micrograms/100 g BW, ip, for 10 days) and 3% calcium chloride in drinking water. The pituitary TSH content of hypercalcemic rats was significantly greater than that of control rats. The results suggest that decreased TSH secretion produced by chronic hypercalcemia is due to diminished TSH release, rather than to decreased pituitary TSH reserve.
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PMID:Thyrotropin secretion in patients with hyperparathyroidism or hypoparathyroidism: effect of serum calcium on thyrotropin release. 640 63

The responses of TSH and PRL to intravenous doses of 500 micrograms of TRH were investigated in 26 patients with primary hyperparathyroidism. Fourteen patients (54%) showed low responses of TSH with peak values of less than 5 microU/ml (Group A). Twelve patients showed normal responses of TSH to TRH (Group B). Among the 26, 12 cases belonging to Group A and eight in Group B were reexamined after the correction of serum calcium level by parathyroidectomy. After successful treatment, the responses of TSH to TRH in six of the 12 patients in Group A returned to normal, whereas those in the remaining six were unchanged. The responses in the eight patients in Group B after surgery were not changed when compared to those before treatment. The basal values of PRL and the responses of PRL to TRH were normal in all patients and did not change after treatment. We showed that patients with primary hyperparathyroidism have a high incidence (54%) of suppressed TSH response to TRH. Hypercalcemia was obviously one of the causative factors in inducing this abnormality in six patients. However, persistently suppressed responses of TSH to TRH were observed in the other six patients in Group A even after the correction of the serum calcium level by surgery. This finding suggests a primary failure of the TSH-regulatory mechanism in some cases of primary hyperparathyroidism.
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PMID:The suppression of TSH in the presence of the normal PRL responses to TRH out of 26 patients with primary hyperparathyroidism. 641 19

To investigate whether chronic endogenous hypercalcemia influences TSH and/or PRL release from pituitary thyrotrophs and lactotrophs in man, 10 patients with endogenous hypercalcemia, due either to cancer or to primary hyperparathyroidism, were injected with 25 micrograms TRH iv. The TSH and PRL responses were compared with those obtained in an age-, sex-, and weight-matched group of patients comprised of 10 normocalcemic individuals with other diseases. The mean maximal TSH response in the hypercalcemic group (3.7 +/- 0.4 microU/ml) was 46% lower than in the normocalcemic group (6.8 +/- 1.2 microU/ml; p less than 0.02). Similarly, the mean maximal PRL response was 45% lower in the hypercalcemic (31 +/- 5 ng/ml) than in the normocalcemic patients (57 +/- 9 ng/ml; p less than 0.05). Feasible mechanisms behind this inhibitory influence of chronic endogenous hypercalcemia on TSH and PRL responsiveness are discussed.
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PMID:Effect of chronic endogenous hypercalcemia on prolactin and thyrotropin responsiveness in man. 644 10