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K Shima

Publications and source records attributed to K Shima.

At least 19 recordsLinked to original sources

Anomeric specificity in the response of gut glucagon-like immunoreactive materials to glucose.

An anomeric specificity of the glucose sensors of A cells and B cells of the pancreas has been reported. In this context the present authors investigated, using the canine intestinal loop prepared from the terminal portion of the ileum, how glucagon-like immunoreactive materials (GLI) of the gut would respond to glucose anomers in an attempt to explore a possible anomeric specificity of glucose-stimulated gut GLI secretion. As a result GLI was found to be more readily released into the blood stream after an intestinal alpha-glucose load than following beta-gluocse during a 15-minute observation period. It is thus suggested that gut GLI-secreting cells have glucose sensors similar to those of pancreatic A or B cells which are specific for the alpha-glucose anomer.

Animals

Half life of gastrointestinal glucagon-like immunoreactive materials.

The composition, half life and hyperglycemic action of the porcine gastrointestinal glucagon-like immunoreactive materials were examined. Glucagon immunoreactivity (GI) measured using specific antiglucagon serum was more abundunt in the extract from the gastric fundus than in the one from the small intestine. When the extract from the gastric fundus was injected in dogs, the half life (T1/2) of total glucagon-like immunoreactivity (total GLI) measured using nonspecific antiglucagon serum was 9.5 +/- 1.1 min (mean +/- SEM), which was longer than that of crystalline pancreatic glucagon, 3.4 +/- 0.2 min, but shorter than that of the extract from the small intestine, 15.9 +/- 1.3 min. On the other hand, T1/2 for GI from the gastric fundus was 5.1 +/- 0.9 min, which was not significantly different from that of crystalline pancreatic glucagon. Blood sugar levels were significantly increased from the basal by 25 +/- 4 mg/100 ml at 10 min and 19 +/- 4 mg/100 ml at 15 min following an injection of the extract from the gastric fundus, but such a change in blood sugar levels was not demonstrated when the extract from the small intestine was injected. These results suggest that GI of the gastric fundus is close to pancreatic glucagon in respect of its metabolism and hyperglycemic activity.

Animals

Chronologic changes of activities of naphthol AS-D acetate esterase and other nonspecific esterases in the mononuclear phagocytes of tuberculous lesions.

Nonspecific esterases of mononuclear phagocytes (MNs) were studied histochemically in the developing and healing tuberculous lesions produced in rabbit skin by bacille Calmette Guérin (BCG). Nonspecific esterases were assayed with the following substrates: naphthol AS-D acetate (AS-D), naphthol AS-D chloroacetate (AS-D Chl), naphthol AS acetate (AS) and alpha-naphthyl acetate (alpha-N), beta-Galactosidase, a lysosomal enzyme of MNs, was also assayed as a marker of MN activation. The number of MNs hydrolyzing AS-D Chl, AS, and alpha-N increased for 2 to 4 weeks after infection. These chronologic changes were similar to that of beta-galactosidase. In contrast, MNs hydrolyzing AS-D appeared predominantly in the healing lesions five to six weeks after infection. These MNs had the morphologic features of balloon-like cells. They contained few lysosomes and gathered in clumps far from the caseous center. The activity of the AS-D esterase was almost completely inhibited by various trypsin inhibitors, but not by the serine esterase inhibitor of phenylmethylsulfonyl-fluoride. These results suggest that the AS-D esterase is a trypsin-like esterase which participates in the healing of tuberculous lesions.

Animals

A-Cell and gut glucagon in normal and depancreatized dogs. Inhibition by somatostatin and insulin.

The effect of somatostatin (SRIF) and of insulin on the plasma levels of immunoreactive glucagon (IRG) and glucose was examined in normal (N) and depancreatized (PX) dogs. The infusion of SRIF (3 microgram/min for 15 min) caused a rapid decrease of the total IRG measured by means of an antiglucanon serum (AGS 10) which cross reacts with extracts of intestinal mucosa. This decrease was due primarily to a fall in the IRG fraction measured by an antiserum (AGS 18) specific for the carboxyl terminus of pancreatic or A-cell IRG. When the dose of SRIF was increased to 10 microgram/min for 90 min, the difference between total and A-cell IRG in the systemic blood also decreased, indicating that other IRG fractions, such as gut IRG, had also been suppressed. The introduction of 50 ml of a 5% glucose solution into a loop of ileum was followed by an increase of gut IRG measured in the regional mesenteric blood. This response was suppressed by the infusion of SRIF (3 microgram/min). Insulin suppressed the basal level of total IRG, but did not alter the gut IRG response to glucose. The SRIF- and insulin-induced reduction in plasma IRG was not associated with a reduction in plasma glucose, suggesting that the high levels of total and A-cell IRG observed in depancreatized dogs were not essential for the maintenance of hyperglycemia.

Animals

[Glucagon-releasing activity of xenopsin, neurotensin and substance P in the perfused rat pancreas (author's transl)].

It has been reported that Xenopsin, Neurotensin and Substance P change plasma glucagon and insulin levels when they are administered in vivo. In order to clarify whether these agents have a direct effect on glucagon and insulin secretion from the pancreas, the action of each substance was examined by using the rat pancreas perfusion technique. The results were as follows: The perfusion with 1 and 5 nmole/min of Xenopsin for ten minutes resulted in a significant but transient release within two minutes. Neurotensin did not show any stimulatory effect on glucagon release in the concentration of 1 or 5 nmole/min for ten minutes. However, Substance P lowered significantly the glucagon concentration in the perfusate in a similar concentration. None of these substances influenced significantly insulin release from the perfused pancreas. These findings suggest that the hyperglucagonemia caused by these three agents in vivo may not be attributed to the direct effect on the pancreatic A-cell.

Animals

Lack of gastrointestinal glucagon response to hypoglycaemia in depancreatized dogs.

Fasting (24 h) normal dogs and depancreatized dogs were injected intravenously with highly purified porcine insulin (Actrapid) in the doses of 0.2 U/kg and 0.5 U/kg, respectively. Blood glucose decreased from 152 +/- 41 (SEM) mg/100 ml to 39 +/- 7 mg/100 ml in the depancreatized dog and from 95 +/- 3 mg/100 ml to 42 +/- 4 mg/100 ml in the normal animal. Using a specific antiserum for "pancreatic" glucagon, the circulating level of glucagon immunoreactivity did not rise from the basal value of 247 +/- 31 pg/ml in the depancreatized group whereas it rose significantly from 223 +/- 24 pg/ml to 321 +/- 41 pg/ml in the normal group. In contrast intravenous infusion of 7 g of arginine increased "pancreatic" glucagon immunoreactivity in both groups. Thus, extrapancreatic glucagon of the pancreatic type does not respond to hypoglycaemia but to arginine infusion.

Animals

Activation of alveolar macrophages exposed to lavage-procured immunoglobulin G obtained from normal rabbit lungs.

Pulmonary washings from rabbits were freed of cells and added to the monolayers of homologous alveolar macrophages (AM). At 1 h after incubation with the pulmonary washings, many more cells adhered to glass, spread out, and showed enhanced Nitro Blue Tetrazolium reduction. The maximal effect of the pulmonary washings on AM activation was obtained 12 h after incubation. The AM activated by the pulmonary washings showed a higher capacity to inhibit the growth of intracellular BCG, and that capacity was correlated with the intensity of Nitro Blue Tetrazolium reduction by the AM. Gel filtration of the pulmonary washings through Sepharose 4B yielded five fractions. The factor that activated the AM functions was in fraction 4. When the immunoglobulin G in the fraction was removed by an immunoadsorbent column, AM activity was abolished. The effect of the immunoglobulin G was dose dependent, and minimal responses to 10(6) cells per ml were obtained at a protein concentration of 20 mug/ml. Lymphokines had no effect on AM activation with respect to the morphological alterations and Nitro Blue Tetrazolium reduction during the 24-h observation time. In summary, AM from normal rabbits were soon activated markedly by lavage-procured immunoglobulin G, but not by lymphokines.

Animals

Effect of secretin on plasma insulin and glucagon in man.

To investigate the effect of physiological doses of secretin on pancreatic A and B cell functions, secretin was infused at a rate of 0.5, 1.0 and 2.0 clinical unit per kg body weight per hr into eight normal men for 30 min or 60 min after an over-night fast, and changes in plasma immunoreactive insulin (IRI) and glucagon immunoreactivity (GI) were measured while monitoring circulating secretin levels by a radioimmunoassay. During the infusion of secretin, the plasma immunoreactive secretin (IRS) levels rose to 140-390 pg/ml which was within a range of the physiological fluctuation in plasma secretin levels reported hitherto. No significant alteration of plasma IRI and GI levels could be demonstrated during these simulated physiologic infusions of secretin. These data suggest that, in humans, the physiological dose of secretin does not influence insulin and glucagon secretion from the pancreas in the basal state.

Adult

Failure of somatostatin to decrease blood glucose by suppression of extrapancreatic glucagon in severely diabetic depancreatized dogs.

Effects of somatostatin on extrapancreatic glucagon secretion in totally depancreatized dogs were examined. Somatostatin infusion at a rate of 3 microgram/min showed a rapid decrease of total glucagon-like immunoreactive materials (total GLI) measured by nonspecific antiserum, AGS 10, and gut glucagon immunoreactivity (gut GI) measured by specific antiserum, AGS 18, in systemic blood. Gut GLI calculated as the difference between total GLI and GI did not decrease significantly within 30 min. No changes of blood glucose were noted. Significant decreases of all glucagon fractions were observed when the rate of somatostatin infusion was increased to 10 microgram/min and prolonged for 90 min, whereas again blood glucose did not change at all. It is concluded that somatostatin inhibits both gut GI and GLI secretion, although gut GLI remains in circulation longer than gut GI. Suppression of gut GI is not effective for the reduction of blood glucose once an extreme hyperglycemia is brought about by insulin deficiency.

Animals

[A case of cerevical canal stenosis accompanied with congenital cervical fusion and extracranial occlusion of vertebral artery--a clinical and embryological study (author's transl)].

A case of cervical canal stenosis accompanied by congenital cervical fusion and extracerebral occlusive disease of the verebral artery was reported. A 39-year-old male was admitted to our hospital on June 5, 1976, because of his shoulder strain, motor weakness and numbness of his left hand, and gait disturbance for a couple of months. Neurological examination disclosed spastic paraparesis with positive pyramidal signs in the four extremities which was greater on the left side, and the superficial and deep sensations were diminished below C-4 dermatomes bilaterally. Spinal tap revealed crystal clear fluid under an initial pressure equivalent to 120 mm of water with a protein content of 20 mg/dl. Plain X-P and laminogram of the cervical spine showed congenital fusion of C 2-3, cervical canal stenosis and cervical spondylosis. Posterior spurring of C 3-4 was demonstrated only on the laminogram. Myelogram showed incomplete myelographic block at the site of C 3-4-5. The left retrograde brachial angiogram disclosed occlusion of the vertebral artery at the site of C3-4. where the proxymal vertebral artery anastomosed with the well developed muscular branch of the vertebral artery, taking a tortuous course at the leve of the transverse foramen of the atlas, and were opacified the distal vertebral artery and basilar artery. Each collateral flow extending from the deep cervical artery and ascending cervical artery anastomosed with the proxymal and distal portion of the occluded vertebral artery. In spite of conservative treatment for two weeks, the cord compression syndromes rather deteriorated. Posterior decompression, that is, C 2-7 laminectomy and C 3-4 partial facetectomy were performed for relieving the symptoms. The postoperative course was uneventfull and there was progressive improvement of the sensory, motor and gait disturbance. The relationship betwen the cervical canal stenosis and cervical spondylosis and their clinco-radiological problem were discussed. The close embryological relationship was very suggestive of the pathogenesis between the cervical bony lesion and congenital cervical fusion and the occlusive vascular lesion of the vertebral artery.

Adult