Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001430 (adenoma)
 21,222 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Light microscopic and immunocytologic investigation revealed focal or diffuse pituitary gonadotroph hyperplasia in 3/27 male and 3/39 female Sprague-Dawley rats over 2 years of age. Three male and 2 female rats exhibited proliferation of morphologically abnormal gonadotrophs which were described as nodules, and 4 male and 5 female rats possessed gonadotroph adenomas which contained both immunoreactive beta-LH and beta-FSH. On plastic sections at the ultrastructural level, a further female rat was found to possess focal gonadotroph hyperplasia, 2 male and 2 female rats, gonadotroph nodules and 2 male and 2 female rats gonadotroph adenomas. While extensive gonadotroph and thyrotroph hyperplasia was observed in the nontumorous portion of the 2 pituitaries harboring thyrotroph adenoma, widespread gonadrotroph hyperplasia was noted in only 2 of 13 pituitaries with gonadotroph adenoma. Gonadotroph adenomas appeared to develop from discrete foci of morphologically altered gonadotrophs. These foci probably then progressed to form nodules and subsequently adenomas. Gonadotrophs within the nodules were often similar in morphology to adenomatous gonadotrophs whereas the earlier, smaller lesions were pleomorphic or more commonly trabecular in appearance. Serum LH levels were measured in some animals. As a group, rats displaying changes in gonadotroph morphology had a higher mean serum LH level than those without these changes, however, the values ranging from 23-249 ng/ml were well within the normal serum LH levels reported in aging rats. Gonadotroph adenomas in human patients have only recently been identified with accuracy and are relatively uncommon. As in the case of rats, they do not appear to arise from a pre-existing end organ hypofunction or pre-existing gonadotroph hyperplasia. A suitable animal model, in the form of spontaneously occurring gonadotroph adenomas in aging rats, might be useful in establishing the etiology, biochemical properties and appropriate therapy for these tumors.
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PMID:Pituitary gonadotroph adenomas in old Sprague-Dawley rats. 393 10

On the basis of a series of hormone estimations in elderly men with a prostatic adenoma, and in men not suffering from the condition (old or young), the authors attempt to develop a physiopathological theory of the pathogenesis of prostatic adenoma. The elderly subject not suffering from a prostatic adenoma has lower blood testosterone, DHT (dihydrotestosterone), LH, FSH and oestrogen levels than the elderly subject with an adenoma, whilst the latter has a lower serum progesterone level. In patients with an adenoma, all the urinary metabolites of testosterone are excreted at markedly higher levels than normal. After prostatectomy, mean serum testosterone and DHT levels fall. In patients undergoing surgery for prostatic adenoma there is a higher level of testosterone and DHT in prostatic venous blood than in the peripheral blood. In prostatic adenoma sufferers, the injection of LHRH results in a higher secretion of LH and FSH than in the control group, but this phenomenon caused an increase in testosterone level only in the controls and not in the adenoma patients. Finally, in all patients with a prostatic adenoma in the absence of stimulation by LHRH, blood testosterone levels were proportional to LH levels. Pathogenic hypothesis: the initial phenomenon could be testicular atrophy in the elderly resulting in the active secretion of gonadotrophins, which themselves would cause a hypersecretion of testosterone and its derivatives within the prostatic tissue itself. It remains to obtain evidence of the existence of gonadotrophins receptor in the prostate, the insensitivity of testicular tissue in the elderly subject to increased gonadotrophin levels and the reasons for which the increased secretion of testosterone by adenomatous prostatic tissue does not in its turn induce inhibition of pituitary hypersecretion of gonadotrophins.
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PMID:[Hormonal disturbances in men with a prostatic adenoma (author's transl)]. 616 Nov 96

Hypersecretion of FSH and alpha-subunit was documented in a man with a pituitary adenoma that was previously diagnosed on clinical grounds as nonfunctioning who had been treated by transsphenoidal surgery and postoperative irradiation. Postoperatively, the patient had high serum FSH levels and normal serum, LH levels. Ten years after the surgery, immunostaining of the tumor revealed the presence of beta FSH, beta LH, and beta TSH in the cytoplasm of scattered adenoma cells, although not always in the same cells. LH levels were elevated during the middle portion of the 12 yr that this patient was followed. However, as LH immunoreactivity was shown (in specimens recently drawn) to be largely due to cross-reactivity in the alpha-subunit RIA, the high LH values may represent high alpha-subunit levels. The elevated FSH levels and alpha-subunit concentrations did not rise after GnRH administration. Thus, during the course of 12 yr, this patient's tumor hypersecreted FSH and alpha-subunit and possibly LH. The evolution of these events may represent the natural history of the tumor or the effects of the therapeutic modalities used. We conclude that adult men with pituitary tumors and complaints of hypogonadism should be evaluated for a FSH-secreting tumor.
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PMID:Follicle-stimulating hormone-secreting pituitary tumor with concomitant elevation of serum alpha-subunit levels. 620 Apr 93

Pituitaries obtained at unselected autopsies of 152 men and women over 80 years of age, dying of different diseases, have been investigated histologically by using various staining procedures, including the immunoperoxidase technique. In 20 pituitaries, 22 adenomas were found providing evidence that these tumors are common in aging subjects. In 9 adenomas out of 17 cases, the immunoperoxidase technique revealed the presence of prolactin, indicating that prolactin-producing adenomas constitute the most frequently occurring pituitary tumor type in old age. The presence of growth hormone was demonstrated in one adenoma which also contained prolactin. No storage of ACTH, FSH, LH or TSH was found in the tumors. The biologic behavior of pituitary adenomas disclosed as incidental findings in old age remains to be elucidated. These neoplasms may have a slower growth rate, but more work is required to establish whether they differ from those found in younger age groups.
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PMID:Pituitary adenomas in old age. 624 45

Recent reports of patients with Cushing's disease who have been explored via the transsphenoidal route indicate that the great majority has pituitary adenomas. We report a patient with biochemically documented pituitary-based hypercortisolism who had a clinical and biochemical remission following hypophysectomy. Serial sections of the pituitary tissue removed showed hyperplasia of corticotroph cells but no adenoma. Hypophysectomy was complete as documented by serum levels of FSH, LH, TSH, prolactin, hGH and ACTH at the lower limits of the respective assays, with no response to appropriate stimuli. This case demonstrates that a minority of patients with Cushing's disease has corticotroph cell hyperplasia without a pituitary adenoma.
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PMID:Pituitary Cushing's disease without adenoma. 625 43

TSH receptor and adenylate cyclase activity of plasma membrane fractions of human thyroid tumors were examined. The mean (+/- SD) basal adenylate cyclase activity in normal thyroid tissues was 0.35 +/- 0.33 nmole/mg protein x 10 min. The activity rose to 280% (range, 270-310%) of basal with TSH (166 mU/ml). In adenomas, the activity rose to 600% (range, 530-650), which was significantly higher than that of normal thyroid (P < 0.005). In the differentiated carcinoma, TSH responsiveness of adenylate cyclase was heterogenous (range, 110-520), but was qualitatively similar to that of the normal thyroid. On the other hand, basal adenylate cyclase activity of undifferentiated carcinoma was significantly lower than that of normal thyroid (0.018 +/- 0.007 nmol/mg protein x 10 min; P < 0.05) and was not stimulated by TSH. LH, FSH, and ACTH did not stimulate the enzyme in either kind of carcinomas. The mean (+/- SD) of the capacity of the high affinity receptor of adenomas (0.72 +/- 0.64 pmol/mg protein) and differentiated carcinomas (0.77 +/- 0.84) was not significantly different from that of normal thyroid (0.92 +/- 0.84). The affinity constants of the receptors in these three tissues were much the same (1.6-2.4 x 10(10) M-1). On the other hand, high affinity receptor could not be detected in all of the undifferentiated thyroid carcinoma. It seems likely that the failure of adenylate cyclase to respond to TSH in undifferentiated carcinoma of the thyroid is due to an alteration at the level of the receptor site. These data suggest that growth and metabolic activity of undifferentiated carcinoma may be independent of TSH, while those of adenoma and differentiated carcinoma may be affected by TSH.
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PMID:Thyrotropin (TSH) receptor and adenylate cyclase activity in human thyroid tumors: absence of high affinity receptor and loss of TSH responsiveness in undifferentiated thyroid carcinoma. 625 3

gamma-Trace, a small protein occurring in body fluids and in secretory and neuroendocrine cells, was demonstrated by immunohistochemical techniques in the cytoplasm of the tumor cells of 13 pituitary adenomas obtained at surgery and autopsy. Seven of the adenomas also contained LH immunoreactivity. FSH, TSH, and ACTH were each found in one gamma-trace-containing adenoma. gamma-Trace was also demonstrated in extracts of 1 pituitary adenoma and of 5 nontumorous adenohypophyses. The immunoreactive protein found in the extracts had a molecular weight and electrophoretic mobility characteristic of gamma-trace. Computerized amino acid sequence comparisons between the primary structure of gamma-trace and those of known hormonal peptides showed no significant similarities.
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PMID:gamma-trace in human pituitary adenomas. 637 15

Ten men who had FSH-secreting pituitary adenomas were evaluated before and 4-6 weeks after transsphenoidal surgery to determine whether reduction of adenoma mass would ameliorate the hormonal abnormalities associated with these adenomas. Nine of the 10 men exhibited marked reduction in adenoma size, as judged by computerized tomography, an 7 had improvement in vision. The same 9 men also had decreases in basal serum FSH concentrations to within the normal range after surgery. The 1 man who had no reduction in adenoma size by computed tomographic scan and whose serum FSH concentration did not decrease to normal after surgery was also the only patient whose abnormal FSH and LH responses to TRH did not improve after surgery. Another man, who had a reduction in adenoma size and serum FSH concentration after surgery, subsequently had regrowth of the adenoma and concomitant resurgence of the FSH concentration. Two men had increases in their serum testosterone concentrations from subnormal to well within the normal range after surgery, suggesting that gonadotroph cell adenomas may impair LH secretion from normal gonadotroph cells. We conclude that the correlation of reduction in adenoma size with reduction in hormonal hypersecretion after surgery suggests that the hormonal hypersecretion is a direct consequence of the adenomatous tissue.
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PMID:Follicle-stimulating hormone-secreting pituitary adenomas: correlation of reduction of adenoma size with reduction of hormonal hypersecretion after transsphenoidal surgery. 640 24

Both gonadotropins are necessary to induce spermatogenesis in man and to recover hypophysectomized males. The patients who suffer from tumoral or traumatic hypothalamo-hypophyseal lesion use to have low endogenous gonadotropins (opposite to hypophysectomized patients), which can produce a minor involution of spermatogenesis. Three patients with postpubertal hypogonadotropic hypogonadism and oligozoospermia were studied. Two of them were operated on for chromophobous adenoma of pituitary, and the other patient had traumatic hypothalamo-hypophyseal lesion. The three patients were treated with 5000 IU HCG/week, associated with testosterone enanthate, in two cases and with bromocryptine in the remaining one. All the patients had normalized spermiogram, but when HCG was interrupted, the sperm count regressed to pretreatment levels in spite of the maintenance of treatment with testosterone or bromocryptine. Minimal amounts of FSH together the testosterone supplied by Leydig cell under the HCG stimulus, are able to recover and maintain the spermatogenesis in these patients.
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PMID:Restoration and maintenance of spermatogenesis by HCG therapy in patients with hypothalamo-hypophyseal damage. 643 47

The nature of the LH abnormality in four men who had gonadotroph cell pituitary adenomas was studied to determine why they had supranormal serum LH concentrations but subnormal or normal serum testosterone concentrations. When basal sera from these four men were subjected to gel filtration chromatography, FSH immunoreactivity eluted principally in the position of intact FSH, but the elution patterns of LH immunoreactivity were biphasic; one peak corresponded to intact LH, and another peak corresponded to the LH subunits, LH beta and alpha. Gel filtration of sera obtained after administration of TRH showed increases in LH immunoreactivity predominantly in the subunits peak. The subunits peak in basal sera consisted principally of alpha, but the percent increase in LH beta in post-TRH sera was greater. When dispersed cells from one gonadotroph adenoma were cultured, medium LH immunoreactivity eluted with the LH subunits. LH beta release into the medium was somewhat greater than alpha initially, but declined more rapidly. We conclude that the apparent hypersecretion of immunoreactive LH of impaired biological activity by four men with gonadotroph cell adenomas represents hypersecretion of LH beta- and alpha-subunits that are uncombined, perhaps because of a structural abnormality or anatomical compartmentalization.
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PMID:Secretion of uncombined subunits of luteinizing hormone by gonadotroph cell adenomas. 643 88


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