Clinical significance of glucagon provocation test in the diagnosis of hypergastrinemia

Glucagon provocation test was performed in the patients with hypergastrinemia and hyperchlorhydria to investigate its diagnostic value. A paradoxical response of plasma gastrin level in the patients with the Zollinger-Ellison syndrome and a marked decrease of plasma gastrin level in the patients with gastric ulcer, duodenal ulcer, excluded gastric antrum, multiple endocrine adenomatosis, pernicious anemia and chronic renal failure were demonstrated by glucagon infusion. Glucagon provocation test, therefore, was considered to be of great value in the diagnosis of the Zollinger-Ellison syndrome, particularly, in the case of an excluded gastric antrum in which secretin provocation test caused the false positive result because of a marked increase of pancreatic secretion. Glucagon provocation test in combination with secretin provocation test, therefore, is at present the most preferable diagnostic procedure for detecting the Zollinger-Ellison syndrome.U

Utilization of N-acetyl-L-tryptophan given intravenously to unrestrained adult rats

The nutritional value of N-acetyl-L-tryptophan (NALT) given intravenously was examined in unrestrained adult rats. They were given solutions of 4% Vuj pattern amino acids, 24.5% glucose, vitamins and electrolytes intravenously for 10 days. They were divided into three groups; one group was then injected intravenously with complete amino acid solution (T group), one with tryptophan-free amino acid solution (TF group) and one group with complete amino acid solution but with NALT instead of tryptophan (NALT). The biological value of the NALT group was 49.6; this value corresponded to 90% of that of the T group. Excretion of injected amino acids totalled about 2.0 to 3.0% in this experiment. The effects of NALT on carcass composition, certain blood constituents and tryptophan pyrrolase activity in the liver were also examined.

Functioning of mitochondria-bound hexokinase in rat brain in accordance with generation of ATP inside the organelle

The function of mitochondria-bound hexokinase, the enzymatic form peculiar to the brain, in utilization of ATP generated inside the organelles, was examined by incubating rat brain mitochondrial fraction with [14C]glucose under various conditions. Addition of succinate and ADP to the incubation medium increased glucose 6-phosphate formation by the mitochondrial hexokinase and caused a smaller increase in ATP concentration in the mitochondria. The glucose phosphorylation was markedly inhibited by the addition of dinitrophenol, potassium cyanide, and oligomycin, and the ATP concentration was decreased. On the other hand, addition of atractyloside suppressed the glucose phosphorylation without affecting the mitochondrial hexokinase activity, whereas addition of antiserum against the mitochondrial hexokinase inhibited both glucose 6-phosphate formation and hexokinase activity. A part of both the glucose phosphorylation and hexokinase activities, however, remained even in the presence of the maximum dose of the anti-hexokinase serum and atractyloside. These results indicate the active utilization of intrinsically generated ATP by the mitochondria-bound hexokinase, a part of which may be located away from the surface of the mitochondrial membrane.

A case of neuraminidase deficiency associated with a partial beta-galactosidase defect. Clinical, biochemical and radiological studies

Neuraminidase deficiency towards fetuin, 2 leads to 3 sialyllactose and 2 leads to 6 sialyllactose was found in cultured skin fibroblasts from a 10-year-old Japanese girl who exhibits craniofacial dysmorphism, a short neck, vertebral and pelvic deformities and macular cherry-red spots. Neuraminidase deficiency in this case seems the primary enzyme defect because the enzyme activity of her parents was intermediate. In addition, beta-galactosidase in leukocytes and cultured skin fibroblasts from the patient was found to be severely deficient, but could be detected in serum and urine. In the parents, beta-galactosidase activity was normal. There were moderately increased levels of urinary sialic acid-rich oligosaccharides and glycopeptides in the patient. The clinical and biochemical observations suggest that this case is very close to mucolipidosis I.