[Mathematical model of the digestion process regulation and its computer presentation]. / Matematicheskaia model' reguliatsii protsessa pishchevareniia i ee komp'iuternaia realizatsiia.

The article presents a mathematic model, which describes regulation of the digestion process. The simulation was based on data on mutual influence of the factors participating in digestion regulation, which were acquired from analysis of over 1200 sources of experimental observations on digestion in dogs published in Russia and abroad, and on own experimental studies. The simulation includes 67 factors and about 400 interactions observed between them. The computer implementation of this simulation demonstrated descriptive coincidence of patterns of the variables respective to the factors of the model with experimental research data; the coincidence was observed in individual patterns and in combined patterns, as well as in coordinated responses in time.

[The adaptational-compensatory reactions of the digestive system during the development of pancreatic atrophy]. / Adaptatsionno-kompensatornye reaktsii pishchevaritel'noi sistemy pri razvitii atrofii podzheludochnoi zhelezy.

Adaptive-compensatory processes have been revealed in the digestive system in pancreatic atrophy. These processes promote: a) the compensation of the pancreatic enzymatic insufficiency and of the cavitary digestion decrease by the alpha-amylase adsorbed at the small intestinal epithelium, b) the increasing of the intestinal pH, c) the keeping up of the postprandial levels of gastrointestinal hormones.

[Pancreatic juice peptides as possible regulators of reparative processes in the pancreas in acute and chronic pancreatitis]. / Peptidy podzheludochnogo soka kak vozmozhnye reguliatory reparativnykh protsessov v podzheludochnoi zheleze pri ostrom i khronicheskom pankreatite.

The experiments were performed on 34 dogs. The subcutaneous injection of boiled pancreatic juice was established to increase the survival of dogs in acute destructive pancreatitis (p < 0.001) and to decrease the specific volume damage to acinar (p < 0.01) and interstitial (p < 0.05) pancreatic tissue. It was also shown that boiled pancreatic autojuice exerted the therapeutic effect in chronic pancreatitis complicated by pancreatic fistulas. Five peptide components with a molecular mass from 4168 D to 1000 were discovered in the canine boiled pancreatic juice by liquid high pressure chromatography. Fractions with a molecular mass between 2187 and 1348 D were found to correspond to biologically active peptides, in particular to somatostatin. It is assumed that the therapeutic effect of boiled pancreatic juice used in acute pancreatitis may be due to somatostatin. Apparently pancreatic juice may turn an efficient therapeutic agent in acute pancreatitis and pancreatic fistulas.

[The functional importance of motilin for the gastrointestinal tract (a review of the literature)]. / Funktsional'noe znachenie motilina dlia zheludochno-kishechnogo trakta (obzor literatury)>

This article reviews the data available at present of the structure of motilin, its localization, species differences and the action on the gastrointestinal tract. Possible mechanisms of motilin release, its participation in the gastrointestinal tract motility as well as its possible physiological role are presented.

[Pancreatic polypeptide (a review of the literature)]. / Pankreaticheskii polipeptid (obzor literatury).

The article is a review of the information available at present of the pancreatic polypeptide (PP) including its structure, localization, stimulators and inhibitors of its release, physiological and pharmacological action on the gastrointestinal tract, mechanisms of PP release in response to a meal and during digestion. The data on PP level in pancreatic diseases are presented as well. The opinion is expressed of PP physiological role in the regulation of gastrointestinal tract functions.

[Effect of the antihypoxic agent isothiobarbamine on gastric secretion]. / Vliianie antigipoksanta izotiobarbamina na zheludochnuiu sekretsiiu.

The experiments on dogs with the isolated Pavlov's ventricles showed that isothiobarbamine (30 mg/kg) in the days of administration decreased the volume of the gastric juice secretion and its total and free activity.

[Nature of correlations among biochemical ingredients of pancreatic juice during digestion in the dog]. / Kharakter korreliatsii mezhdu biokhimicheskimi ingredientami podzheludochnogo soka v protsesse pishchevareniia u sobak.

In pancreatic atrophy the coordination of acinar and ductal cells activity as well as their functioning are disturbed. The subcutaneous injections of boiled pancreatic juice maintained correlations between pancreatic juice proteolytic and alpha-amylolytic activities and between volume and bicarbonate concentrations separately, but didn't restore their coordination.

[Physiological and biochemical characteristics of changes in pancreatic secretory activity during the development of atrophy in dogs]. / Fiziologo-biokhimicheskaia kharakteristika izmenenii sekretornoi aktivnosti pozdheludochnoi zhelezy v protsesse razvitiia ee atrofii u sobak.

In pancreatic atrophy the normal digestive dynamics of pancreatic juice volume, concentrations and outputs of proteolytic enzymes, alpha-amylase and bicarbonate are disturbed. The changes of enzymic dynamics are revealed before those of pancreatic juice volume and bicarbonate concentration. The subcutaneous injections of boiled pancreatic juice didn't restore dynamics of indices studied but maintained their levels during the more prolonged period.

[Relationship between the concentrations of pancreatic polypeptide, gastrin, and motilin in blood plasma in pancreatic atrophy]. / Sootnosheniia mezhdu kontsentratsiiami pankreaticheskogo polipeptida, gastrina i motilina v plazme krovi pri atrofii podzheludochnoi zhelezy.

The results suggest that in the pancreatic atrophy the interrelations of gastrointestinal hormones are changed. These changes may be involved in the maintenance of the relatively high hormonal responses to feeding in the pancreatic atrophy.

[Histological changes in the duodenal mucosa in pancreatic atrophy]. / Gistologicheskie izmeneniia slizistoi obolochki dvenadtsatiperstnoi kishki pri atrofii podzheludochno zhelezy.

Chronic experiments on dogs have shown that pancreatic atrophy development and decreased secretion of the pancreas are associated with atrophic alterations in the duodenal mucosa, bearing resemblance to the picture of chronic duodenitis. During subcutaneous injections of boiled pancreatic juice the pancreatic atrophy development was delayed and the duodenal mucosa looked almost normal. Hyperplasia of Brunner's glands was revealed in the course of pancreatic atrophy development. There is every reason to regard hyperplasia as a compensatory-adaptive process directed at the maintenance of pH level and mucoprotein intestinal concentration.

[Concentration of pancreatic polypeptide, gastrin, and motilin in the plasma of dogs during the digestive process in pancreatic atrophy]. / Kontsentratsiia pandreaticheskogo polipeptida, gastrina, i motilina v plazme krovi sobak v protsesse pishchevareniia pri atrofii podzheludochnoi zhelezy.

Fasting and postprandial concentrations of pancreatic polypeptide, gastrin and motilin were measured during 2hrs after meat feeding. The byphasic rise of pancreatic polypeptide concentration occurred in 15 and 120 min and increase of gastrin concentration--in 15 min after feeding. Increase of motilin concentration occurred during the second hour. These findings complete our previous data and suggest that hormonal mechanisms involved in postprandial response are maintained even in pancreatic atrophy.

[Similarities and differences in the behavior of pancreatic polypeptide, gastrin, and motilin in dog blood plasma during the development of pancreatic atrophy]. / Skhodstvo i razlichie v povedenii pankreaticheskogo polipeptida, gastrina i motilina v plazme krovi sobak v protsesse razvitiia atrofii podzheludochoi zhelezy.

One-hour postprandial responses of plasma concentrations of pancreatic polypeptide, gastrin and motilin were measured in 4 dogs during 31 months of pancreatic atrophy development, produced by obstructing their pancreatic juice flow. Basal pancreatic polypeptide and gastrin concentrations decreased, while motilin concentration did not. During this period the animals displayed a significant postprandial response. These findings suggest that hormonal mechanisms involved in the digestive process are maintained in the period of the sharp disturbance of the pancreatic exocrine function.

[Pancreatic atrophy: its effect on the plasma concentration of pancreatic polpeptide, gastrin and motilin in dogs]. / Atrofiia podzheludochnoi zhelezy: ee deistive na kontsentratsii pankreaticheskogo polipeptida, gastrina i motilina v plazme krovi u sobak.

One hour postprandial responses of plasma concentrations of pancreatic polypeptide, gastrin and motilin were detected in healthy dogs. Pancreatic atrophy was produced in these animals by obstructing their pancreatic juice flow. Basal hormone concentrations in four animals did not change significantly during 11 months of pancreatic atrophy. During this period the animals displayed a significant postprandial response. These preliminary results suggest that hormonal mechanisms involved in the digestive process are maintained during pancreatic atrophy.