[The characteristics of isolated and intact portions of the small intestine in rats in chronic experiments]. / Kharakteristika izolirovannogo i neizolirovannogo uchastkov tonkoi kishki krys v khronicheskikh éksperimentakh.

Comparison of the velocities of glucose and fructose absorption with the maltose hydrolysis in isolated and functioning portions of the small intestine revealed the quantitative characteristics of the latter portion to be superior of the isolated one. The data on the water balance in the perfused portion of the small intestine was obtained.

[The effect of starvation on carbohydrate transport in the mouse and rat small intestine]. / Vliianie goloda na transport uglevodov v tonkoi kishke myshei i krys.

The starvation-related changes of glucose and maltose absorption were shown to be unrelated to absorption of sucrose and lactose. The glucose and maltose transport responds synchronously to starvation and refeeding. The total reduction of the mice body mass after refeeding occurred in 48 hrs. The effect of a preliminary load of the gastrointestinal tract on the transport rate in enzyme-transport system, is discussed.

[The effect of food and drug herbal extracts on the hydrolysis and transport of sugars in the rat small intestine under different experimental conditions]. / Vliianie ékstraktov pishchevykh i lekarstvennykh trav na gidroliz i transport sakharov v tonkoi kishke krys pri razlichnykh éksperimental'nykh usloviiakh.

Viola tricolor, Frigonella foenum-graecum, Laurus nobilis were shown to reduce the glucose transport. The same was true for extract of tea leaves. Fructose did not affect the velocity of free glucose absorption, slightly reduced the velocity of sucrose hydrolysis and absorption of produced hexoses and water. Participation of active transport of carbohydrates in absorption processes occurring both in vitro and in vivo, is discussed.

[Free choice of salt solutions and functional enzyme-transport mechanisms of the small intestine in relation to different calcium levels in the body]. / Svobodnyi vybor solevykh rastvorov i funktsionirovanie fermentativno- transportnykh mekhanizmov tonkoi kishki pri razlichnoi obespechennosti organizma kal'tsiem.

The data obtained suggest the coordinated changes in the rat free choice of the solutions, which differ in Ca+(+)-content, and sensitivity of the enterocyte transport systems for glucose under the influence of chronic Ca-tropic treatment. Response of the glucose channel and maltose enzyme-transport to such a treatment is stated to be of the specific character.

[The characteristics of the action of calcium antagonists on glucose transport in the rat small intestine]. / Osobennosti deistviia antagonistov kal'tsiia na transport gliukozy v tonkoi kishke krys.

Ca antagonists reduced intestinal glucose transport in vitro and in vivo. The Ca-channel blocking agent verapamil (B) and calmodulin inhibitors chlorpromazine, triftasine (I) exerted rather unequal effects on glucose transport: B exerting a weaker effect on the transport from serosa than I. B and Ca-free medium reduced Vmax with no changes at Km as opposed to I. Under the influence of EDTA (5 mmol/l) there only is an unsaturated glucose transport. Ca- and calmodulin-affinity sites seem to play a major role in the regulation of enterocyte glucose transport system.

[Correlation of the behavioral characteristics of animals with varying levels of alcohol motivation: motor activity, taste and electrical pain sensitivities]. / Korreliatsiia povedencheskikh kharakteristik zhivotnykh s razlichnym urovnem alkogol'noi motivatsii: dvigatel'noi aktivnosti, vkusovoi i élektrobolevoi chuvstvitel'nosti.

It is shown that rats with a high degree of orienting-investigatory behaviour, low thresholds of emotional and pain sensitivity consume considerably more ethanol and rejected substances--urea and mustard--in comparison with low-active, less electrical pain-sensitive animals with a low degree of alcohol motivation. It is suggested that studying of characteristics of specialized appetite can be an important factor for prognostication of behaviour and role of individual in population.

[Effect of papaverine on monosaccharide and glycine transport in the small intestine in vitro]. / Issledovanievliianie papaverina na transport monosakharidov i glitsina v tonkoi kishke in vitro.

Papaverin is shown to have a significant inhibitory effect on the intestinal transport systems for glucose, galactose and glycine but not for fructose. In vitro experiments have revealed that the inhibitory effect of papaverin on the glucose transport take place under mucosal application, nevertheless the serosal one is of a stimulatory character. Papaverin inhibits only the active component of the glucose transport.

[The fenazepam demand by rats depending on the degree of alcoholic motivation]. / Potreblenie fenazepama krysami v zavisimosti ot stepeni alkogol'noi motivatsii.

Phenazepam stimulates the drinking behaviour of rats. Under free-choice conditions ethanol-preferring rats drank significantly greater amount of phenazepam solution than those not preferring ethanol. Intraperitoneal administration of phenazepam and ethanol eliminated differences between the animals of the two groups in consumption of each substance but had no cross effect.

Membrane digestion and transport under physiological conditions: a review of available data.

A technique to study membrane digestion and transport in the small intestine under physiological conditions has been developed. The technique is based on a continuous perfusion of a chronically isolated loop of the rat small intestine. Membrane hydrolysis and transport of some nutrients in the rat small intestine in chronic, as well as in acute (in situ) experiments was investigated. The absorption of hexoses and amino acids has been found to be 2.5-4 times higher under physiological conditions than in acute in situ experiments. Both the active transport of glucose released from maltose hydrolysis and the hydrolysis of the latter is increased under physiological conditions. A coupling between the final stages of hydrolysis and the initial stages of transport in chronic experiments was shown to be highly efficient; practically all or nearly all glucose released is being transported without entering the luminal phase. The hydrolysis rate of starch during the perfusion of a small intestinal segment in chronic experiments is many times higher than that in acute experiments or under anaesthesia. The enzymatic and transport activities revealed using a widely accepted technique in situ, the more so, in vitro account for only a small fraction of those which are typical of undisturbed processes under conditions close to the physiological. The levels of functioning of the digestive-transport systems of the small intestine considered as natural levels developed in the process of evolution, actually reflect only residual processes and, in most cases, they account for 1/3 to 1/10 of the true level of an actual physiological process.

[Glycerinized models of enterocytes and several of their properties]. / Glitserinizirovannye modeli énterotsitov i nekotorye ikh svoistva.

The method for the preparation of glycerol-treated models of the enterocytes with preserved membrane has been described. Using such a simplified model of the enterocyte suspension allows membrane digestion and enzyme properties to be studied. Moreover, preserving the important properties of the native isolated cells the glycerol-treated enterocytes have a number of essential advantages as compared with other known preparations of the small intestinal mucosa. Some characteristics of the glycerol-treated models of the enterocytes have been described in the paper.

Membrane and intracellular hydrolysis of peptides: differentiation, role and interrelations with transport.

The possible relative importance of the membrane and intracellular peptidases of the enterocytes in splitting dietary peptides to amino acids has been analysed. On the anoxic criterion, membrane hydrolysis was found to be predominant. Model experiments revealed cooperative interactions between the membrane enzyme and the coupled transport system. This cooperativity allows the main characteristics of oligomer transport to be described in terms of membrane digestion. Comparison of the behaviour of membrane and intracellular peptidase under different conditions has shown that the former are largely involved in digestion and the latter in intracellular metabolism. It is suggested that the efficiency of the membrane system is high enough to account for the hydrolysis of protein, especially taking into account the stimulation of enzyme processes in the brush border that occurs after ingestion of protein and carbohydrate. A sequential model based on the concept of three interacting enzyme layers (glycocalyx, lipoprotein membrane and cytosol) is presented.