Linked Life Data

19194773

Source:http://linkedlifedata.com/resource/pubmed/id/19194773

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-2-23
pubmed:abstractText
The pathogenesis of primary hyperparathyroidism (I degrees -HPT) and secondary hyperparathyroidism (II degrees -HPT) remains to be elucidated. To characterize their pathophysiology, we investigated the effects of calcium and phosphate on cell proliferation and PTH release in an organ culture of parathyroid tissues. Dissected parathyroid tissues obtained from patients with I degrees -HPT (adenoma) or II degrees -HPT (nodular hyperplasia) were precultured on a collagen-coated membrane for 1-4 week. After changing the medium for one containing various concentrations of phosphate, PTH release and [(3)H]thymidine incorporation were studied. In contrast to dispersed parathyroid cells cultured in a monolayer, calcium decreased PTH release in a concentration-dependent manner in parathyroid tissues. Furthermore, when parathyroid tissues obtained from II degrees -HPT were precultured for 1-4 weeks, PTH release and parathyroid cell proliferation were significantly increased in high-phosphate medium. These phosphate effects were also observed to a lesser extent in parathyroid tissues obtained from I degrees -HPT, but there was no significant difference between I degrees -HPT and II degrees -HPT. Microarray analyses revealed that mRNA levels of PTH, CaSR, and VDR were well preserved, and several growth factors (e.g. TGF-beta1-induced protein) were abundantly expressed in II degrees -HPT. Using organ cultures of hyperparathyroid tissues, in which PTH release and CaSR are well preserved for a prolonged period, we have demonstrated that phosphate stimulates parathyroid cell proliferation not only in II degrees -HPT but also in I degrees -HPT. Although the mechanism responsible for phosphate-induced cell proliferation remains to be elucidated, our in vitro findings suggest that both parathyroid tissues preserve to some extent a physiological response system to hyperphosphatemia as observed in normal parathyroid cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0914-8779
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
224-33
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Stimulating parathyroid cell proliferation and PTH release with phosphate in organ cultures obtained from patients with primary and secondary hyperparathyroidism for a prolonged period.
pubmed:affiliation
Department of Medicine, Institute of Clinical Endocrinology, Tokyo Women's Medical University, Kawada-cho 8-1, Shinjuku-ku, Tokyo 162-8666, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't