[Plasma ACTH and Nelson tumors in bilaterally adrenalectomized Cushing patients]

Stress augmented ultraviolet-irradiation-induced pigmentation

It was reported that adrenocorticotropic hormone stimulates melanogenesis in cultured melanocytes. Stress (high population density and restraint stress) induced a significant increase in adrenocorticotropic hormone levels in plasma and skin compared to control. The serum obtained from HR-1 x HR/De F1 female mice subjected to stress showed significantly increased tyrosinase activity in human melanocytes compared to that from nonstressed mice. The increase in tyrosinase activity was inhibited in the presence of 10 nM corticostatin, an adrenocorticotropic hormone inhibitor. The aim of this study was to examine whether adrenocorticotropic hormone released into the circulation under stressful conditions is associated with the regulation of ultraviolet-induced pigmentation. Mice divided into three groups were housed for 22 d under the following conditions: five mice per cage (control); 10 mice per cage (high population density); restraint stress 4 h per d. The animals were exposed to ultraviolet-B irradiation (72 mJ per cm2, thrice per wk). After ultraviolet-B irradiation, delayed tanning was marked in stressed mice. The number of dihydroxyphenylalanine-positive melanocytes also significantly increased in stressed animals. Pretreatment with 100 microg of corticostatin inhibited the augmentation of the stress-induced pigmentary response and the increase in dihydroxyphenylalanine-positive melanocytes after ultraviolet irradiation. Adrenocorticotropic hormone released by stress may activate tyrosinase in melanocytes, resulting in the augmentation of ultraviolet-induced pigmentation. These results suggest that adrenocorticotropic hormone is at least partly responsible for the sensitivity of the pigmentary response after ultraviolet irradiation under stressful conditions.

Trans-sphenoidal microsurgical treatment of Nelson's syndrome

Clinical features and the operative results in the author's personal series of ten cases with Nelson's syndrome are presented. There were nine females and one male patient with ages ranging from 20 to 44 years (mean 36 y). All patients presented with typical hyperpigmentation of the skin and had abnormally raised plasma ACTH levels. X-ray polytomography detected sellar abnormalities in 80% of the cases. Computerized tomography was positive for pituitary tumour in three patients. Trans-sphenoidal microsurgical removal of Nelson's ACTH adenomas were successful in seven of ten patients. The operative technique of radical-selective resection to achieve endocrinological cure is described. Pertinent literature is reviewed and the incidence of Nelson's syndrome, an issue of controversies regarding the pathogenesis, and the management of Nelson's adenomas are discussed.

Malignancies of the endocrine glands

Patients with malignant tumors of the endocrine system can be effectively treated by surgery, the 5 year survival rate varying between 30-90 per cent, depending on organ involvement. In the Federal Republic of Germany, 1 out every 5 persons dies as a result of malignancy. Less than 1 per cent of the total annual rate of such deaths relates to malignancies originating in the endocrine glands.