|
KMID : 1007020030010020105
|
|
Korean Soceity of Osteroporosis
2003 Volume.1 No. 2 p.105 ~ p.112
|
|
|
A Diagnosis by Expression and Modulation of the Parathyroid Hormone (PTH)/PTH-Related Peptide Receptor in Skin Fibroblasts from 2 Patients with Pseudohypoparathyroidism Ib
|
|
Jeong Won-Jea
Woo Jeong-Taek
Kim Byung-Joon
Park Cheol-Young
Oh Seung-Joon
Kim Jin-Woo
Kim Young-Seol
Suh Kwang-Sik
Yang In-Myung
An Kyu-Jeong
Oh Ki-Won
Ihm Sung-Hee
Park Sung-Woo
Kim Sung-Woon
|
|
|
Abstract
|
|
|
Objectives: Pseudohypoparathyroidism(PHP) is a heterogenous disease complex characterized by resistance to parathyroid hormone(PTH). These patients were hypocalcemic and hyperphosphatemic. PHP Ia patients have reduced activity of the stimulatory G protein associated with adenylate cyclase. So they are resistant to other hormones in addition to PTH and have the phenotypic feature of Albright’s hereditary osteodystrophy. In contrast, subjects with PHP Ib have a normal appearance, normal Gs activity, and resistance to PTH only. Since skin fibroblasts are relatively easily obtained and could reflect responsiveness to PTH, we compared agonist & PTH stimulated cAMP production and expression of PTH/PTHrP receptor messenger ribonucleic acid in skin fibroblasts from control and PHPIb subjects.
Methods: Cultured human skin fibroblasts possess a PTH receptor and respond to PTH with an increase in cAMP production. We compared agonist and PTH stimulated cAMP production in fibroblast from normal and two PHP Ib subjects. To explore the possibility that defects in expression of PTH/PTH-rP receptor mRNA in skin fibroblasts, we used a reverse transcriptase polymerase chain reaction(RT-PCR).
Results: In control fibroblasts, stimulation of cAMP production by PTH and expression of PTH/PTHrP receptor mRNA was easily detectable and was not significantly affected by dexamethasone pretreatment. In fibroblasts from Case 1 and Case 2 demonstrating reduced PTH-induced cAMP production and the level of basal PTH/PTHrP receptor mRNA was also reduced. But dexamethasone slightly reversed reduced PTH-induced cAMP production in fibroblasts from Case 2.
Conclusion: In all conditions where only PTH-induced cAMP production by PHP-Ib fibroblasts was reduced, the abnormality could be explained by the reduced level of PTH/PTHrP receptor mRNA in these cells. And we will use this method to differenciate pseudohypoparathyroidism type.
|
|
|
KEYWORD
|
|
|
Pseudohypoparathyroidism, Parathyroid Hormone, Fibroblast
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|