| pubmed-article:2507734 | pubmed:abstractText | The dynamics of growth hormone (GH) and prolactin (PRL) secretion in response to intravenous 400 micrograms thyrotropin-releasing hormone (TRH) in 13 untreated patients with pituitary adenomas (6 women, 7 men; ages 20-64 years; 8 patients with acromegaly, 3 prolactinomas and 2 non-functional adenomas) were correlated with the results of immunohistochemical studies of GH and PRL in the adenoma cells. The basal serum GH concentrations were abnormally high in 6 and normal in 2 cases of acromegaly. In 5 of 6 acromegalic patients with pure GH-containing adenomas, TRH stimulated GH release by less than 100%. One patient with acromegaly and pancreatic islet cell carcinoma had the maximum increment for GH by 303%. TRH stimulated GH release by more than 100% in 2 acromegalic patients with mixed GH/PRL-containing adenomas. In 3 patients with prolactinoma and in 2 patients with non-functional adenoma the basal GH levels were 0.5 mU/L or undetectable and there was no GH response to TRH. The peak serum PRL levels after TRH were less than 100 ng/ml in 6 acromegalic patients with pure GH-containing tumors and in 2 patients with non-functioning pituitary tumors, and were more than 230 ng/ml in 3 patients with prolactinoma and in 2 acromegalic patients with mixed GH/PRL-containing tumors. It is suggested that the TRH test may help clinically in establishing the diagnosis of prolactinoma, pure GH-secreting tumors and mixed GH/PRL-containing tumors. | lld:pubmed |
