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Biomedical subjects

T Kanno

Publications and source records attributed to T Kanno.

At least 577 records · Page 32Linked to original sources

Plasma secretin level and exocrine pancreatic secretion in response to intraduodenal infusion of 1-phenyl-1-hydroxy-n-pentane and HCl by using a new four lumen tube.

We have designed a four lumen tube which has enabled us to aspirate duodenal juice while infusing endogenous stimuli into the lower part of duodenum. Exocrine pancreatic secretion and plasma immunoreactive secretin (IRS) levels have been simultaneously observed in response to intraduodenal infusion of 1-phenyl-1-hydroxy-n-pentane (PHP) and 0.1 N HCl in normal subjects, patients with diabetes mellitus and patients with chronic pancreatitis by use of this tube. (1) Pancreatic flow rate and bicarbonate concentration were found to increase to twice those of basal levels and plasma IRS levels rose significantly after infusion of PHP or HCl in normal subjects. The same tendency was observed in patients with diabetes mellitus. (2) Exocrine pancreatic secretion did not change after infusion of PHP or HCl in patients with chronic pancreatitis. Pancreatic flow rate, bicarbonate concentration and amylase output were significantly low in patients with diabetes mellitus. (3) Pancreatic flow rate and bicarbonate concentration incresed to about twice those of basal levels after both PHP and HCl infusion. On the other hand, although pancreatic amylase output increased significantly after infusion of HCl as compared with basal secretion, it did not change after infusion of PHP. It appeared reasonable to conclude that PHP is a morespecific substance for releasing secretin than HCl.

Adolescent↗

Mouse spleen cell populations involved in the mitogenic response to protein A.

In this paper, we examined the cellular components involved in the mitogenic response of mouse spleen cells to protein A. The mitogenic response was almost abrogated by the removal of macrophages. The abrogated response could be restored by the addition of peritoneal exudate macrophages from syngeneic mice. The reconstitution experiments were carried out for studying the populations of lymphocytes responding to protein A. In these experiments, spleen cells were passed through a Sephadex G-10 column and then they were separated into nylon-wool-adherent and nonadherent cells. The nylon-wool-nonadherent cells were used as T cells. The nylon-wool-adherent cells were used as B cells after they were treated with anti-BAT and complement. These results indicated that both B and T cells responded to protein A, and T-B cell cooperation could possibly play some role in the response.

Animals↗

Cold acclimation in the secretory responses of the isolated exocrine pancreas of the rat.

1. The secretory function of the isolated and perfused exocrine pancreas has been studied in the course of cold acclimation in rats that were fed at an ambient temperature of 1 degrees C in an artificial climatic room.2. A series of experiments was carried out in early autumn (autumn series). The sums of the outputs of protein, amylase, zymogen protease, lipase, and juice flow in samples collected for a total of 30 min during and after 5 min stimulation with different concentrations of cholecystokinin-pancreozymin (CCK-PZ; 5-50 m-u./ml.) were simultaneously measured in the autumn series of experiments, and they were plotted against the logarithmic scale of concentration of CCK-PZ to obtain a dose-response relation.3. The sums of protein output, lipase output, and juice flow evoked by different concentrations of CCK-PZ in the group of rats fed at 1 degrees C for 3 weeks were almost identical to the corresponding value in the group fed at about 21 degrees C for 3 weeks.4. The sum of output of zymogen protease in the former group was almost identical to the corresponding value in the latter group except that the sum induced by 20 m-u. CCK-PZ/ml. was significantly larger in the former.5. The sum of output of amylase induced by various concentrations of CCK-PZ in the former group was significantly smaller than the corresponding value in the latter group.6. It was thus concluded that the CCK-PZ-induced outputs of protein, lipase, and zymogen protease were little affected if any by 3 weeks of cold exposure, whereas the CCK-PZ-induced amylase output was significantly suppressed.7. Another similar series of experiments was performed in the summer of the same year. The results obtained suggest that the secretory function of exocrine pancreas is directly inhibited by prolonged cold exposure in summer but it is not in autumn.

Acclimatization↗

CT in evaluation of the circle of Willis.

The method of visualizing the circle of Willis intentionally on contrast-enhanced CT scan was studied. The incidence of circle of Willis in our series was 86%. Only mild side effects were observed, in 7.5% of cases. CT of 60 proven cerebral aneurysms were reviewed and aneurysm was detected in 57%. This method has the potential to be a noninvasive screening procedure for evaluation of suspected cerebral aneurysm, as well as evaluation of marked arteriosclerosis, occlusion of major arteries, and mass effect of parasellar tumors.

Cerebral Angiography↗

Enzyme histochemical and electron microscopic study of a virilizing adrenocortical adenoma.

Enzyme histochemical and ultrastructural studies of a "dexamethasone-suppressed" virilizing adrenocortical adenoma and the attached cortex revealed that tumor cells showed little activities of some lysosomal enzymes and scarcity of lipofuscins and dense bodies of lysosomal type, forming a marked contrast to the cells of zona reticularis and the virilizing adenomas previously reported. The other findings of tumor cells, such as a pattern of activities of dehydrogenases including 3beta-hydroxysteroid dehydrogenase and the morphology of mitochondria, were those of reticularis cells. The findings showed that scantiness of lipofuscins did not rule out the possibility of adenoma producing adrenal androgen, dehydroepiandrosterone. Most of the tumor cells as well as reticularis cells were positive for alkaline phosphatase, the activity of which was interpreted as the effect of ACTH stimulation.

3-Hydroxysteroid Dehydrogenases↗

Influence of external potassium concentration on secretory responses to cholecystokinin-pancreozymin and ionophore A23187 in the pancreatic acinar cell.

1. The inhibitory effect of a diminution in [K+]o on the secretory processes of the pancreatic acinar cell was analysed in the isolated and perfused rat pancreas. 2. Partial replacement of KCl with NaCl produced falls in both amylase output and pancreatic juice flow which were induced by 5 m-u. cholecystokinin-pancreozymin (CCK-PZ)/ml., and the responses were slowly regained after reintroduction of a standard concentration of KCl. 3. A quantitative relation was found between the amount of amylase released by CCK-PZ and [K+]o over the range 1.0--5.6 mM. A linear relation was obtained between the ratio of E1K+]3(0)/amylase output and [K+]3(0). 4. A quantitative relation was also found between the pancreatic juice flow induced by CCK-PZ and [K+]o over the range 1.0--5.6 mM. A linear relation was obtained between the ratio of [K+]3(0)/juice flow and [K+]3(0). 5. The results obtained may be explained by a model as follows: (1) amylase output and juice flow induced by CCK-PZ are simply proportional to the amount of complex composed of a carrier molecule bearing one Ca and four Na atoms, (2) the inward movement of the complex is tightly linked to the CCK-PZ-induced activation of pumps which are postulated on both basal and apical sides of the membrane of the acinar cell, and (3) the Na:K coupling ratio of the pumps is close to 3:2. 6. A quantitative relation was also found between the amount of amylase released by Ca reintroduction after pre-treatment with Ca-ionophore A23187 and [K+]o. This may be explained by a model essentially similar to that mentioned above. 7. Total replacement of NaCl with NaBr slightly reduced the CCK-PZ-induced fluid and amylase secretion. Total replacement of NaCl with sodium isethionate or with sodium pyruvate, however, virtually abolished the CCK-PZ-induced fluid and amylase secretion.

Amylases↗

Influences of extracellular calcium and potassium concentrations on adrenaline release and membrane potential in the perfused adrenal medulla of the rat.

Prolonged perfusion of isolated rat adrenal glands with high K produced a transient increase in adrenaline release that reached a maximum within 1 min and then declined with a half-time of about 5 min. The higher the [K]o used, the larger was the release of adrenaline elicited. There was a linear relation between the mean rate of adrenaline release in the initial 5 min of continuous stimulation with excess K and logarithmic increase in the [K]o. The higher the [Ca]o used, the steeper was relation obtained: the slope determined in the presence of 5 mM-Ca was nearly twice as much as that obtained in the presence of 0.5 mM-Ca. The release of adrenaline in response to excess K was virtually abolished by the omission of [ca]o. The chromaffin cells were depolarized in proportion to logarithmic increase in the [K]o. Linear relations were thus obtained between the mean rates of adrenaline release and the membrane potential of chromaffin cells in the presence of different [Ca]o. Application of high K revived secretory response of a gland after prolonged exposure to acetylcholine in the presence of tetrodotoxin, when adrenaline release had declined below a half of the maximum response. Application of acetylcholine also revived secretory response after prolonged exposure to high K. These results support the view that the mechanism of Ca influx activated by high K may differ from that activated by acetylcholine.

Adrenal Medulla↗