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)

The effects of histamine on cAMP accumulation and parathyroid hormone (PTH) release were studied in dispersed cell preparations from pathological parathyroid tissue of 13 patients with primary hyperparathyroidism. Histamine stimulated cAMP accumulation 1.4- to 110-fold in a dose- and time-dependent manner. The increased cAMP content was inhibited by the H2 antagonist cimetidine and the H1 antagonist promethazine, with Ki values of 0.14--0.46 and 0.2--0.37 micrometer, respectively. Moreover, in one cell preparation, the H2 agonist dimaprit stimulated cAMP accumulation 2- to 3-fold, while the H1 agonist 2-pyridylethylamine had no effect on cAMP levels. The potent alpha-and beta-adrenergic antagonists phentolamine and propranolol did not inhibit histamine-stimulated cAMP accumulation significantly. Histamine also caused a dose- and time-dependent increase in PTH release, with a Ka in reasonable agreement with that for cAMP accumulation (0.5--1 vs. 3 micrometer, respectively), indicating that enhanced cAMP accumulation was linked to increased secretion. These results indicate that pathological human parathyroid cells have histamine receptors, probably H2 in subtype, which mediate enhanced cAMP accumulation and PTH release.
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PMID:Histamine receptors on dispersed parathyroid cells from pathological human parathyroid tissue. 625 3

We studied in vitro the presence of histamine and the effect of histamine and its antagonists on cAMP accumulation in parathyroid tissue (parathyroid adenoma or hyperplasia) from patients with primary hyperparathyroidism. Parathyroid adenomatous tissue contained 11.2 +/- 2.9 ng histamine/g wet weight (approximately 2 X 10(-5) M), as determined by a specific radioenzyme assay. Histamine caused a prominent increase in cAMP accumulation in parathyroid tissue slices in a dose-dependent manner, with half-maximal stimulation being achieved at 5 X 10(-6) M and maximal stimulation occurring at 10(-4) M histamine. The histamine H2 receptor antagonists, cimetidine and metiamide, caused profound inhibition of histamine-stimulated cAMP accumulation in the parathyroid tissue. Pyrilamine, an H1 antagonist, also inhibited histamine-stimulated cAMP accumulation. Isoproterenol, a beta-adrenergic agonist, elicited marked elevation of cAMP, and its stimulatory effect was blocked by propranolol, but the effects of histamine on cAMP levels in parathyroid tissue were not blocked by propranolol. Histamine significantly stimulated (an increase of 50%) the release of immunoreactive parathyroid hormone. The present observations demonstrate that parathyroid adenomatous tissue has a relatively high content of histamine, and the release of immunoreactive parathyroid hormone from this tissue. The effects of antagonists suggest that histamine stimulates cAMP accumulation in the parathyroid adenomatous tissue by an action on both H2 and H1 histamine receptors.
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PMID:Histamine and human parathyroid adenoma: effect on adenosine 3',5'-monophosphate accumulation in vitro. 626 86