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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of bromocriptine and somatostatin on hormone secretion and the ultrastructure of human pituitary adenomas was studied in vitro. Prolactin secretion was inhibited by bromocriptine in 3 out of 10 prolactin-secreting tumours and in explants from 2 normal pituitaries. GH secretion was reduced by bromocriptine in 4 out of 6 GH-secreting adenomas but was not affected by the drug in the incubations of normal pituitaries. Somatostatin inhibited GH secretion in 2 out of 5 pituitary adenomas and the effect was comparable with that of bromocriptine. Incubation of prolactin-secreting adenomas with oestradiol for as long as 24 days produced no change in hormone secretion. Examination of tumour explants by electron microscopy showed that somatostatin and bromocriptine produced accumulation of secretion granules but no changes in the secretory organelles. Long term bromocriptine treatment of "nude" athymic mice bearing xenografts of human pituitary adenomas suppressed hormone secretion and produced some increase in secretion granules but there were no morphological changes in the secretory organelles or other vital structures of the adenoma cells.
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PMID:Effect of bromocriptine, somatostatin, and oestradiol-17 beta on hormone secretion and ultrastructure of human pituitary tumours in vitro. 611 72

Prolactin-secreting adenoma is probably the most common functional pituitary tumour in type I multiple endocrine neoplasia (MEN I). The authors report on a case of gastrinoma and parathyroid adenoma associated with prolactinoma. The latter tumour was revealed by sudden pituitary apoplexy. The characteristic features of endocrine tumours in MEN 1 are discussed, and the relevant literature is reviewed. Emphasis is placed on the fact that prolactinomas are well tolerated, remain clinically silent for a long time and may be diagnosed only when dramatic symptoms suddenly appear.
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PMID:[Type I multiple endocrine neoplasia with prolactin-secreting tumor revealed by pituitary apoplexy (author's transl)]. 611 57

Prolactin (PRL) concentration was estimated in milk and blood of women with various types of galactorrhea (n = 53) and was compared with lactating (n = 17) and normally menstruating women (n = 36). Mean milk (+/- SD) PRL concentration in lactating women (160 +/- 66 micrograms/l) was similar to that of galactorrhea due to pituitary adenoma (149 +/- 87 micrograms/l, n = 24), thyroid dysfunction (193 +/- 72 micrograms/l, n = 8), functional causes (192 +/- 91 micrograms/l, n = 10) or recent pregnancy (198 +/- 44 micrograms/l, n = 2), but higher than that of sex steroid-induced galactorrhea (85 +/- 53 micrograms/l, n = 9). Plasma PRL concentration in lactating women (208 +/- 102 micrograms/l) was higher than in normal control women (14 +/- 5 micrograms/l) and patients with galactorrhea due to thyroid dysfunction (36 +/- 15 micrograms/l), functional causes (16 +/- 8 micrograms/l), drugs (20 +/- 4 micrograms/l), recent pregnancy (22 +/- 3 micrograms/l) or pituitary adenoma (145 +/- 53 micrograms/l). The milk to plasma PRL concentration ratio was 0.8 +/- 0.4 in lactating women and 1.1 +/- 0.7 in patients with adenoma but significantly higher (p = 99% two-sided) in galactorrhea due to thyroid dysfunction (4.4 +/- 2.1), drugs (3.4 +/- 1.1) or functional causes (12.3 +/- 4.3). Bromocriptine administration reduced PRL in both fluids. It is concluded that in women with galactorrhea milk PRL concentration is similar to that of nursing mothers, but plasma levels of this hormone are significantly lower than that of the latter group in all but the pituitary adenoma related galactorrheas.
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PMID:Prolactin concentration in milk and plasma of puerperal women and patients with galactorrhea. 654 14

Prolactin (PRL) and other pituitary hormones (luteinizing hormone, follicle-stimulating hormone, growth hormone [GH], thyrotropin stimulating hormone) were measured before, during, and after transphenoidal pituitary adenomectomy in 16 patients with hyperprolactinemia. The diagnosis of prolactinoma was made in three of the 16 patients by the absence of PRL response to thyrotropin-releasing factor (TRF) and a dopamine receptor antagonist, metoclopramide, without radiologic evidence of an adenoma. Contrary to findings in subjects with normal PRL values, the PRL rise in response to anesthesia and operation was absent. Other pituitary hormones, with the exception of GH, which increased during anesthesia and operation, exhibited no acute changes. In 11 of 16 cases, complete tumor removal was achieved as determined by the rapid decline of PRL levels to normal values within 24 to 48 hours after operation and by subsequent clinical follow-up. This finding documents that the adenoma is the main source of excessive PRL secretion. The circulating half time of immunoreactive PRL determined by frequent sampling in these patients was variable, ranging from 74 to 190 minutes, significantly longer than the previously reported value of 15 minutes determined by bioassay. Although a transient decline was evident, serum PRL levels remained elevated in those patients with incomplete tumor removal. These findings suggest that a single measurement of serum PRL within 24 to 48 following transphenoidal adenomectomy is a reliable indicator of the success or failure of the procedure.
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PMID:Changes in pituitary hormones during and following transsphenoidal removal of prolactinomas. 676 67

Prolactin secreting adenomas are the most frequently (50%) occurring pituitary adenoma. They occur more commonly in women than in men (4:1). Impairment of gonadal function accounts for the predominant symptoms in both sexes. Forty females and ten males with prolactin secreting adenomas were treated with selective adenoma removal by transsphenoidal surgery. Duration of symptoms varied from two months to 25 years. Twenty percent of the women and 100% of the men had invasive adenomas, a tumor that is difficult or impossible to eradicate. The chances of surgically correcting hyperprolactinemia in the female patient was 75% if the preoperative basal prolactin was 200 ng/ml or less, or 71% if the adenoma was non-invasive. The men were more difficult to treat because they all had invasive adenoma. In 50% of the men, prolactin was normalized by surgery. Early recognition of these patients before the adenomas become invasive is needed.
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PMID:Prolatin secreting pituitary adenomas. 678 11

Five primary human pituitary tumor cell cultures were initiated from adenoma fragments obtained from patients with prolactin-secreting adenomas and acromegaly. Functional cell cultures were maintained and propagated in monolayer or suspension culture for up to 9 months. Optimal cell viability and growth were achieved using Ham's F10 medium enriched with 20% fetal bovine serum, although cells from a patient with acromegaly also grew in serum-free, defined, hormone-containing medium. Bromocriptine (100 ng/ml) did not alter the growth curve of replicating cells derived from a patient with acromegaly. These cells initially secreted 5.5 micrograms human growth hormone/10(6) cells, and hormone production diminished after 6 wk. Prolactin secretion by cells derived from prolactinomas (0.5 to 1.3 micrograms/10(6) cells/24 h) was stimulated by thyrotropin-releasing hormone (10 ng/ml) in two of the cultures. Both dopamine (10 ng/ml) and nickel chloride (1 mM) suppressed PRL secretion. These studies demonstrate that responsive human pituitary tumor cell cultures can be initiated and maintained.
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PMID:Establishment of functional human pituitary tumor cell cultures. 682 Jun 53

Therapeutic results in 80 cases of pituitary prolactin adenomas, grouped according to Hardy's neurosurgical classification, are discussed as a function of the 5 types of treatment administered. These were: selective adenomectomy by the trans-sphenoidal approach under microscopic supervision; bromocriptine usually at doses of 5 to 7.5 mg per day; combined surgery and radiotherapy (50 to 60 grays 5 times per week for 5 to 6 weeks); surgery plus bromocriptine; surgery plus radiotherapy plus bromocriptine. Selective adenomectomy gives excellent results in stages 1 and 2, if performed by an experienced surgeon. Bromocriptine was remarkably effective in all cases, whatever the level of blood prolactin and the size of the adenoma. Prolactin levels never returned to normal after radiotherapy, which also markedly increased the frequency of post-therapeutic hormonal insufficiencies.
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PMID:[Recent advances in post-therapeutic hormonal surveillance of prolactin adenomas (author's transl)]. 706 87

Described is a two-chromatographic-step preparative-scale technique for the purification of human prolactin from a frozen pituitary homogenate. The method utilizes hydrophobic interaction chromatography on the mildly hydrophobic adsorbent phenyl-Sepharose CL-4B and anion-exchange chromatography on DEAE-cellulose in the presence of acetonitrile. Human prolactin was solubilized at pH10.0 after a prior extraction of pituitaries at pH4.0, the acid pH being ineffective at solubilizing human prolactin but capable of solubilizing large amounts of interfering protein. An 11-fold increase in the potency of the solubilized human prolactin was achieved in this manner. Prolactin could be adsorbed to phenyl-Sepharose at low ionic strengths (I<0.01); few other proteins were adsorbed under these conditions. This is a demonstration of the hydrophobic nature of human prolactin. The amount of phenyl-Sepharose was limited to the minimum (35mg of protein/g of phenyl-Sepharose) necessary to adsorb human prolactin, further reducing the uptake of other pituitary protein. Desorption was achieved by using an acetonitrile gradient (0-30%, v/v), resulting in a purification of human prolactin of 85-fold and recovery of 78%. Acetonitrile (20%, v/v) was also included in all buffers for DEAE-cellulose chromatography, increasing the resolution and recovery of human prolactin, apparently by minimizing non-ionic interactions with the matrix. Prolactin (10mg) was recovered from 63g if pituitaries, an overall recovery of 58%. It was homogeneous by gel filtration and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, contained less than 0.1% somatotropin (growth hormone), on iodination demonstrated more than 95% binding to excess anti-(human prolactin) serum and could be displaced from anti-(human prolactin) serum in a manner indistinguishable from the serum of a patient with a human prolactin-secreting adenoma.
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PMID:Hydrophobic-interaction chromatography and anion-exchange chromatography in the presence of acetonitrile. A two-step purification method for human prolactin. 734 Aug 23

During the last four years 12 Prolactin (PRL) secreting adenomas whose first clinical manifestation appeared before the age of 15 years have been studied. The first signs were a decreased growth rate and arrest of pubertal development in 4 girls and 2 boys in whom the adenoma occurred before or during puberty. In the other six cases (5 girls and 1 boy) the first signs were secondary amenorrhea and galactorrhea in girls and in the boy gynecomastia followed by galactorrhea. Symptoms of the tumour (headaches, and visual disturbances) were almost invariable (11/12) and led to the diagnosis in two cases. Plasma PRL levels were always elevated (80 to more than 5,000 ng/ml) and did not rise in response to TRH. 11 out of 12 were large tumours and pituitary tomography showed that tumour was circumscribed in five cases and invasive in the other seven. The prognosis is related to the short term outcome. The condition may be cured by surgery only (25% cases only) or by surgery and bromocriptine.
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PMID:[Prolactin adenomas in children (author's transl)]. 739 49

The paper presents follow-up results of narrow-beam proton therapy (1000 MeV) in 75 female patients suffering from prolactin-secreting pituitary adenomas. Prolactin concentrations reduced both in macro- and microprolactinomas patients. The response was achieved in 96% of the cases in adenoma stages I-IIIa. Such results are superior to those reached with other treatment modalities. The efficacy of the above proton treatment can be raised by adjuvant use of chemotherapy.
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PMID:[Results of proton therapy in the treatment of pituitary prolactin-secreting adenomas]. 780 84


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