Pituitary adenomas

Many of these intracellular events are critical to the prohferative effects of CXCL12. For example, the CXCL12-induced effect on proliferation is dependent on calcium. Pre-treatment of pituitary adenoma cells with BAPTA-AM abohshes the CXCL12-induced increase in prohferation (Florio et al. 2006). The increase in proliferation also requires activation of Erk 1/2, as pre-treatment with PD98059, a MEK inhibitor, blocks the proliferative effect of CXCL12, and this is correlated with a decrease in Erk 1/2 phosphorylation. Similarly, the proliferative effects of... 

O Surgical resection of the pituitary tumor through transsphenoidal pituitary microsurgery is the treatment of choice for most patients with growth hormone-producing pituitary adenomas. 

Vasomotor symptoms, as well as other menopausal symptoms, occur in over 50% of perimenopausal women and over 80% of menopausal women.5 Menopausal symptoms tend to be more severe in women who undergo surgical menopause compared with natural menopause because of the more rapid decline in estrogen concentrations. Women who seek medical treatment should undergo laboratory evaluation to rule out other conditions that may present with similar symptoms, such as abnormal thyroid function or pituitary adenoma. Once other conditions have been excluded, HRT should be considered. 

Rieder CL, Palazzo RE 1992 Colcemid and the mitotic cycle. J Cell Sci 102 387-392 Saez C, Japon MA, Ramos-Morales F et al 1999 hpttg is over-expressed in pituitary adenomas and other primary epithelial neoplasias. Oncogene 18 5473—5476... 

ACTH-dependent Cushing s syndrome is usually caused by overproduction of ACTH by the pituitary gland, causing adrenal hyperplasia (Cushing s disease). Pituitary adenomas account for about 80% of these cases. Ectopic ACTH-secreting tumors and nonneoplastic corticotropin hypersecretion are responsible for the remaining 20% of cases. 

TSH-secreting pituitary adenomas are diagnosed by demonstrating lack of TSH response to thyrotropin-releasing hormone stimulation, inappropriate TSH levels, elevated TSH a-subunit levels, and radiologic imaging. 

Most patients with pituitary failure (secondary hypothyroidism) have clinical signs of generalized pituitary insufficiency such as abnormal menses and decreased libido, or evidence of a pituitary adenoma such as visual field defects, galactorrhea, or acromegaloid features. 

Patients who were irradiated for 5 weeks with photons of 8 MV of energy at 3 Gy/min, for nasopharyngeal carcinoma or pituitary adenoma, became less sensitive to odors. Their thresholds for amylacetate and eugenol were determined before and several times after radiotherapy. One week after irradiation, the thresholds had increased from 10 to 2 dilution steps. Sensitivity recovered over the subsequent weeks, reaching 6-8 dilution steps 6 months after treatment. The dose received by the olfactory area was estimated as 2Gy/day (Ophir etal, 1988). 

Jin L, Maeda T, Chandler WF, Uoyd RV (1993) Protein kinase C (PKC) activity and PKC messenger RNAs in human pituitary adenomas. Am J Pathol 142 569-578 Johnstone RW, Cretney E, Smyth MJ (1999) P-glycoprotein protects leukemia cells against caspase-dependent, but not caspase-independent, cell death. Blood 93 1075-1085... 

Clinically significant pituitary disease is rare, although small functionless pituitary adenomas are commonly seen as incidental findings at autopsy or on magnetic resonance brain scans. The main issues for clinical pharmacology concern replacement therapy for hypopituitarism, and treatment of hormone-producing pituitary adenomas. 

Unlabeled Uses Treatment of cocaine addiction, hyperprolactinemia associated with pituitary adenomas, neuroleptic malignant syndrome... 

Hyperprolactinemia (idiopathic or primary pituitary adenomas) PO 0 25 mg 2 times... 

A 1978 WHO report quoted an unpublished study by March in which pituitary adenomas were found in 26% of women with secondary amenorrhea following the use of oral contraceptives, yet in only 13% of cases who had not used these products (118). The difference was significant, but selection bias might have explained the results. 

Matsuura I, Saeki N, Kubota M, Murai H, Yamaura A. Infarction followed by hemorrhage in pituitary adenoma due to endocrine stimulation test. Endocr J 2001 48(4) 493-8. 

Mastronardi, L., Guiducci, A., Spera, C., Puzzilli, F., Liberati., and Maira, G. 1999. Ki-67 labelling index and invasiveness among anterior pituitary adenomas Analysis of 103 cases using the MIB-1 monoclonal antibody./. Clin. Pathol. 52 107-111. 

Castro, M.G., Cowen, R., Smith-Arica, J., Williams, J., Ali, S., Windeatt, S. et al. (2000) Gene therapy strategies for intracranial tumours glioma and pituitary adenomas. Histol. Histopathol., 15, 1233-1252. 

Triphenyltin hydroxide caused dose-related cystoid changes in the pars intermedia of the pituitary gland for male and female mice administered this compound for 52 or 104 weeks at doses of 0.3-6.2 mg/kg/day (Tennekes et al. 1989a). Up to 40% of the males and 80% of the females were affected at 52 weeks by the highest dose. At the end of 104 weeks, 72.3% of the high dose males and 55.6% of the females exhibited the cystoid changes. The lower incidence in females at 104 weeks related to a high early mortality from fatal pituitary adenomas (see Section 2.2.2.8). 

There is also no conclusive evidence that inorganic tin compounds have carcinogenic properties. However, there are data which indicate that organotin compounds (bis(tributyltin)oxide and triphenyltin hydroxide) may be tumorigenic at low levels of tin. Bis(tributyltin)oxide (2.5 mg/kg/day) and triphenyl tin hydroxide (0.3-6.2 mg/kg/day) were associated with pituitary adenomas in rats of both sexes with exposures of 104-106 weeks. When triphenyltin hydroxide was administered, the pituitary adenomas were present only in the females and contributed to decreased longevity. 

In the studies of long-term exposure of rats to both triphenyltin hydroxide and bis(tributyltin)oxide, most of the tumors were found in endocrine glands. In addition to the pituitary adenomas associated with bis(tributyltin)oxide and triphenyltin hydroxide, there was also an increased incidence of pheochromocytomas of the adrenal gland, parathyroid carcinomas and pancreatic adenocarcinomas in animals from at least one sex. Triphenyltin hydroxide was associated with an increased incidence of testicular Leydig cell tumors in male rats at the highest dose. Hepatic tumors were found in male and female mice following 80 weeks of triphenyltin hydroxide administration. 

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