scholarly journals Comparison of the development of proteolytic activity in the abomasum of the preruminant calf with that in the stomach of the young rabbit and guinea-pig

1973 ◽  
Vol 30 (2) ◽  
pp. 285-296 ◽  
Author(s):  
M. J. Henschel
Keyword(s):  
Guinea Pig ◽  
Proteolytic Activity ◽  
Post Partum ◽  
Stomach Contents ◽  
Young Rabbit ◽  
Main Peak ◽  
Adult Rabbit ◽  
Guinea Pig Stomach ◽  
High Level ◽  
Protease Secretion

1. Proteolytic activity was measured in the abomasal contents of five calves during the first 7 weeks of life and in the stomach contents of rabbits and guinea-pigs during the first 4 weeks of life.2. The pattern of protease secretion in the abomasum varied considerably among individual calves; in addition to rennin, some pepsin activity was found in most animals from the first sampling at 9 d of age.3. Only pepsin was secreted in the guinea-pig stomach from birth, at a consistently high level at all ages.4. The main peak of proteolytic activity in the rabbit stomach during the 1st week post partum had an optimum at pH 3·5–4·0, corresponding to that for calf rennin. During the 3rd week of life the main pepsin peak, with an optimum at pH 1·6–2·0, developed.5. Agarose gel electrophoresis of an extract of neonatal rabbit stomach mucosa showed the activity peak at pH 3·5–4·0 to be due to two slow-moving components of mobilities similar to that of crystalline rennin. At least one of these cross-reacted with antiserum to crystalline rennin.6. At 10 d and 3 weeks of age, activity at pH 1·6–2·0 was due to two faster-moving proteases, one being the main pepsin of the adult rabbit, which moved at the same speed as crystalline porcine pepsin, with the antiserum of which it cross-reacted.

scholarly journals Regulation of acetylcholine release from the guinea-pig stomach via 5-HT4 receptors.

1994 ◽  
Vol 64 ◽  
pp. 90
Author(s):  
Shogo Matsuyama ◽  
Hideyo Sakjyama ◽  
Koji Nei ◽  
Shigenori Katayama ◽  
Norikazu Sakamoto ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Acetylcholine Release ◽  
Guinea Pig Stomach

Cell loss from human, canine and guinea-pig gastric mucosa measured by DNA radioimmunoassay

1984 ◽  
Vol 66 (6) ◽  
pp. 701-708 ◽  
Author(s):  
B. C. Hurst ◽  
W. D. W. Rees ◽  
A. Garner
Keyword(s):  
Guinea Pig ◽  
Animal Species ◽  
Colorimetric Assay ◽  
Cell Loss ◽  
Mucosal Cell ◽  
Normal Human ◽  
Dna Loss ◽  
Guinea Pig Stomach ◽  
Pavlov Pouch ◽  
Stimulation Of

1. A DNA radioimmunoassay, sensitive in the range 25–1000 ng, has been developed to measure gastric mucosal cell loss. Validity of the assay was based on antibody specificity, absence of interference from gastric contents, parallel tracer displacement by dilutions of gastric and standard DNA, and crossover with colorimetric assay. 2. With this assay, gastric DNA shedding was examined in two animal species and man. In the guinea-pig stomach, DNA loss was 20–100 pg/h and in the canine Pavlov pouch, 260–580pg/h. In the canine Pavlov pouch stimulation of acid secretion by histamine and exposure to exogenous acid increased DNA output. In the normal human stomach DNA loss was 544 k 175 pg/h and in duodenal ulcer patients, 649 k 225 pg/li. 3. DNA radioimmunoassay provides a sensitive and reproducible measure of cell exfoliation from the stomach and may be a useful tool for studying aspects of gastric mucosal defence.

Actions of cysteinyl leukotrienes in the enteric nervous system of guinea-pig stomach and small intestine

2003 ◽  
Vol 459 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Sumei Liu ◽  
Hong-Zhen Hu ◽  
Chuanyun Gao ◽  
Na Gao ◽  
Guodu Wang ◽  
...  
Keyword(s):  
Nervous System ◽  
Small Intestine ◽  
Guinea Pig ◽  
Enteric Nervous System ◽  
Cysteinyl Leukotrienes ◽  
Guinea Pig Stomach

Capsaicin-induced release of substance P-like immunoreactivity from the guinea-pig stomach

1988 ◽  
Vol 22 (1-2) ◽  
pp. 156
Author(s):  
D. Renzi ◽  
P. Santicioli ◽  
C.A. Maggi ◽  
C. Surrenti ◽  
A. Calabrò ◽  
...  
Keyword(s):  
Substance P ◽  
Guinea Pig ◽  
Guinea Pig Stomach

scholarly journals FURTHER STUDIES ON THE ROLE OF PROTEASES IN THE ALLERGIC REACTION

1961 ◽  
Vol 113 (2) ◽  
pp. 359-380 ◽  
Author(s):  
Georges Ungar ◽  
Takuso Yamura ◽  
Jacqueline B. Isola ◽  
Sidney Kobrin
Keyword(s):  
Amino Acid ◽  
Guinea Pig ◽  
Proteolytic Activity ◽  
Guinea Pigs ◽  
Protease Activity ◽  
Amino Acid Esters ◽  
Protein Substrates ◽  
Protease Activation ◽  
Acid Esters

Protease activity was measured through the hydrolysis of synthetic amino acid esters in body fluids and tissues of guinea pigs, rats, mice, and humans. Significant in vitro activation was observed in serum and lung slices of sensitized guinea pigs on addition of the specific antigen. Increased proteolytic activity was also seen in reverse anaphylaxis. More marked activation occurred when guinea pig serum was treated with peptone and guinea pig or rat serum was treated with agar. Protease activation was demonstrated in specimens of human skin under the influence of a poison ivy extract or croton oil added in vitro. Urinary protease activity of guinea pigs increased significantly during the first hours of anaphylactic shock and very markedly in peptone shock. Peptone shock, elicited in mice pretreated with H. pertussis, was accompanied by a considerable increase in protease activity in the peritoneal fluid as compared with non-pretreated mice which were insensitive to peptone. Proteolytic activity resulting from the activation procedures was due to a number of proteases. The dominant substrate affinity and inhibition patterns suggest that serum and urine proteases are similar to but not identical with plasmin. Anaphylactic activation exhibited patterns different from those resulting from the action of anaphylactoid agents. Tissue enzymes are either of cathepsin- or chymotrypsin-type or mixtures of both. Some of the activated enzymes, although remarkably effective in hydrolyzing amino acid esters, show no activity on protein substrates. This does not justify, however, their designation as "esterases." They probably belong to the class of specific proteases acting only on a single or a small number of functionally significant protein substrates. There is at present sufficient evidence to prove not only that protease activation does occur in anaphylaxis and anaphylactoid conditions but also that it is an important component of the chain of reactions leading to the allergic response.

scholarly journals Neuronal release of endogenous dopamine from corpus of guinea pig stomach

1997 ◽  
Vol 273 (5) ◽  
pp. G1044-G1050
Author(s):  
Kazuko Shichijo ◽  
Yasuko Sakurai-Yamashita ◽  
Ichiro Sekine ◽  
Kohtaro Taniyama
Keyword(s):  
Guinea Pig ◽  
Ganglion Cells ◽  
Splanchnic Nerve ◽  
Muscle Layer ◽  
Nerve Fibers ◽  
Endogenous Dopamine ◽  
Dopamine Content ◽  
Release Of Acetylcholine ◽  
Gastric Corpus ◽  
Guinea Pig Stomach

Neuronal release of endogenous dopamine was identified in mucosa-free preparations (muscle layer including intramural plexus) from guinea pig stomach corpus by measuring tissue dopamine content and dopamine release and by immunohistochemical methods using a dopamine antiserum. Dopamine content in mucosa-free preparations of guinea pig gastric corpus was one-tenth of norepinephrine content. Electrical transmural stimulation of mucosa-free preparations of gastric corpus increased the release of endogenous dopamine in a frequency-dependent (3–20 Hz) manner. The stimulated release of dopamine was prevented by either removal of external Ca2+ or treatment with tetrodotoxin. Dopamine-immunopositive nerve fibers surrounding choline acetyltransferase-immunopositive ganglion cells were seen in the myenteric plexus of whole mount preparations of gastric corpus even after bilateral transection of the splanchnic nerve proximal to the junction with the vagal nerve (section of nerves between the celiac ganglion and stomach). Domperidone and sulpiride potentiated the stimulated release of acetylcholine and reversed the dopamine-induced inhibition of acetylcholine release from mucosa-free preparations. These results indicate that dopamine is physiologically released from neurons and from possible dopaminergic nerve terminals and regulates cholinergic neuronal activity in the corpus of guinea pig stomach.

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