Linked Life Data

19029774

Source:http://linkedlifedata.com/resource/pubmed/id/19029774

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2008-11-25
pubmed:abstractText
Growth hormone-releasing hormone (GHRH) stimulates not only the synthesis and secretion of GH but also the proliferation of normal somatotrophs. The expression of GHRH receptor (GHRHR) is regulated by GHRH, both of which are known to be expressed in human GH-secreting pituitary adenoma cells. Somatic mutations in the subunit of Gsalpha protein (gsp), lead to the constitutive activation of adenylyl cyclase in pituitary adenomas that secrete GH. It has not been examined how gsp mutations influence GHRHR expression in GH-secreting adenomas. We therefore analyzed the expression levels of GHRHR messenger ribonucleic acid (mRNA) in GH-secreting pituitary adenomas focusing on a gsp mutation. Furthermore, we investigated the effect of GHRH on the expression of GHRHR mRNA in primary cultures of GH-secreting pituitary adenoma cells. GHRHR mRNA expression levels were significantly elevated in gsp mutation-positive GH-secreting adenomas compared with those in gsp mutation-negative ones. In primary-cultured GH-secreting adenoma cells, the increase of GH secretion in response to GHRH was shown in both gsp mutation-positive and -negative adenoma cells with a significantly higher response in the latter adenoma cells. GHRH increased GHRHR mRNA expression level in gsp mutation-negative adenoma cells while it was not influenced by GHRH in gsp mutation-positive adenoma cells. These results suggest that gsp mutations up-regulate GHRHR mRNA expression in GH-secreting pituitary adenoma cells, and that gsp mutations desensitize the adenoma cells to GHRH in terms of their GHRHR mRNA expression probably because of their saturation of GHRH signaling.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1349-8029
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
481-7; discussion 487-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:19029774-Acromegaly, pubmed-meshheading:19029774-Adenoma, pubmed-meshheading:19029774-Adult, pubmed-meshheading:19029774-Amino Acid Substitution, pubmed-meshheading:19029774-Cell Line, Tumor, pubmed-meshheading:19029774-Female, pubmed-meshheading:19029774-GTP-Binding Protein alpha Subunits, Gs, pubmed-meshheading:19029774-Gene Expression Regulation, Neoplastic, pubmed-meshheading:19029774-Growth Hormone-Releasing Hormone, pubmed-meshheading:19029774-Humans, pubmed-meshheading:19029774-Male, pubmed-meshheading:19029774-Middle Aged, pubmed-meshheading:19029774-Mutation, Missense, pubmed-meshheading:19029774-Neoplasm Proteins, pubmed-meshheading:19029774-Nerve Tissue Proteins, pubmed-meshheading:19029774-Pituitary Neoplasms, pubmed-meshheading:19029774-Point Mutation, pubmed-meshheading:19029774-RNA, Messenger, pubmed-meshheading:19029774-RNA, Neoplasm, pubmed-meshheading:19029774-Receptors, Neuropeptide, pubmed-meshheading:19029774-Receptors, Pituitary Hormone-Regulating Hormone
pubmed:year
2008
pubmed:articleTitle
Elevation of growth hormone-releasing hormone receptor messenger ribonucleic acid expression in growth hormone-secreting pituitary adenoma with Gsalpha protein mutation.
pubmed:affiliation
Department of Neurosurgery, Nippon Medical School, Tokyo, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't