[The inhibitory effect of tolbutamide on both secretions of cortisol in the adrenal cortex and of prolactin in the pituitary gland (author's transl)]

It has been frequently postulated that insulin-induced hypoglycemia is widely employed clinically to assess the function of the hypothalamo-pituitary axis, being known to stimulate several pituitary trophic hormones such as HGH, ACTH, PRL (Prolactin), etc. Although tolbutamide produces hypoglycemia through the increase of endogenous insulin secretion, in the present study tolbutamide was used instead of insulin, and the effect of tolbutamide on the secretion of PRL from the pituitary gland and also on the secretion of cortisol from the adrenal cortex as well as HGH was studied, using 44 healthy normal subjects (male 35 and female 9, from 15 approximately 75 years of age). (1) PRL : One gram of tolbutamide injected into 5 normal subjects did not increase the serum concentration of PRL up to 120 minutes after the administration of the drug, while the concentration of PRL in the serum was increased clearly by the injection of insulin (0.1U/kg), with maximum PRL levels (approximately 50pg/ml) occurring at 60 minutes after the insulin administration. These results indicated strongly that tolbutamide inhibited the secretion of PRL from the pituitary gland. (2) Hypothalamo-Pituitary-Adrenal cortex : The same dose of tolbutamide as in the PRL experiment was also injected intravenously, and changes of serum cortisol levels were measured until 180 minutes after the injection of tolbutamide. It was found that levels of serum cortisol were clearly depressed within 30 minutes, and then the cortisol values started to increase up to 120 minutes after the administration of tolbutamide. The stimulatory effect of ACTH on the secretion of cortisol from the adrenal cortex was also strongly abolished by tolbutamide in the early phase as stated above. The data suggest that tolbutamide might have a direct inhibitory effect on the adrenal cortex as well as on pituitary PRL secretion.

Chondroitin 4- and 6-sulfaturia: a new type of inborn error of metabolism?

A 14-year-old boy was found to excrete excessive amounts of acidic glycosaminoglycans which were predominantly chondroitin 4-sulfate and chondroitin 6-sulfate. Clinical features included dwarfism, mental retardation, coarse facies, deformities of the spine, hip joints and thorax, and granulations in leucocytes. The clinical and biochemical features found in this boy were compared with the known types of mucopolysaccharidosis and it has been concluded that this case is a new type of mucopolysacchariduria.

Chondroitin 4- and 6-sulfate mucopolysaccharidosis--a morphological study

A 17-year-old patient clinically manifesting gargoyle face, dwarfism, skeletal bone deformity, mild mental retardation and benign course was presented. Biochemically, increased urinary excretion of acidic glycosaminoglycans was confirmed and chondroitin 4-sulfate and chondroitin 6-sulfate were substantiated to be the major components of the acid mucopolysacchariduria. Light microscopically, variable numbers of foam cells were observed in the biopsy materials of the lymph nodes, liver and skin, as well as in the smears of bone marrow aspirates. In the liver, the parenchymal cells appeared vacuolated. Histochemically, accumulation of sulfated acid glycosaminoglycans was demonstrated in the cytoplasm of the foam cells proliferating in these tissues, as well as in the liver cells. Electron microscopically, all of these storage cells were found to contain numerous, membrane-bound, vacuolar inclusions filled with flocculent, finely reticulogranular materials of low electron density similar to those seen in the storage cells of Hurler, Hunter or Sanfilippo's syndrome. Empty vacuoles were often coexistent. Accordingly, this case should be termed "chondroitin 4- and 6-sulfate mucopolysaccharidosis", with emphasis on the possibility of a new type of genetic mucopolysaccharidosis.