Secretion gastric juice

Contraction of smooth muscle Biosynthesis of steroid hormones Gastric juice secretion... 

Its most important pharmacological effects are dilation of veins and capillaries, increased permeability of capillaries, increased heart rate, contraction of nonvascular smooth musculature (constriction of bronchi, gastrointestinal tract peristalsis), stimulation of gastric juice secretion, and release of catecholamines from adrenal glands. 

Traditional or Hj antihistamine drugs block many effects caused by histamine however, it turns out that they are not able to withstand events mediated by H2 receptors, in particular excess gastric juice secretion. In 1977 an H2-receptor antagonist, cimetidine, was proposed, which revolutionized stomach ulcer treatment. Later on, ranitidine was proposed, followed by drugs with minor structural and pharmacological differences such as famotidine and nizatidine. 

Cimetidine is a representative of first-generation antihistamine drugs that block H2 receptors. The main pharmacological effect of cimetidine is the suppression of gastric juice secretion associated with H2 receptors of the stomach walls. It suppresses both basal and stimulated hyckochloric acid produced by food as well as histamine and gastrine, which simultaneously lower pepsin activity. 

Orexin A (from the Greek orexis, "appetite") is a 33 amino acid neuropeptide connected by two disulfide bridges. Orexin A is a powerful stimulant forfood intake and gastric juice secretion. Scientists are studying orexin A to learn more about the regulation of appetite and eating, hoping to learn more about causes and potential treatments for anorexia nervosa. 

Q4 List the components of gastric secretion and the approximate volume of gastric juice secreted per day. 

Fig. 17. Relative and absolute concentrations of uronic acid, total hexosamine and excess hexosamine in spontaneously secreted mucus and in gastric juice secreted in response to sham feeding and to histamine.

Wl. Wada, T., Clinical studies on gastric juice secretion. Japan J. Med. 1, 293-315 (1962). 

The formation of (149) involves nucleophilic addition of sulfamide (136) across the carbon-nitrogen triple bond of (150), followed by tautomerisation of the initial iminoproduct (Scheme 61). A series of analogous N-sulfamoylamidines in which the length of the chain between the thiazole nucleus and the amidine moiety was varied also inhibited gastric juice secretion.7... 

Influence of Feeding on the Quantity and the Composition of the Gastric Juice Secreted. — First of all, it has been established that there exists a very definite relation between the secretorial functions and the food absorbed. Thus Chigin, by measuring the quantity of gastric juice which flows after the ingestion of various foods, has found ... 

Dayb Quantity of meat Gastric juice secreted Acidity frecHC5l Pepsin in ICC Total content in pepsin... 

Figure 4-1. Volume (Menge), acidity (Aziditat), and egg white digestion (Eiweissver-dauung) of gastric juice secreted by a dog s Pavlov pouch in response to sham feeding. Each vertical line marks a 5-minute interval. At X the dog was shown a cat. (From Bickel A. Experimentelle Untersuchungen uber den Einfluss von Affekten auf die Magensaftsekretion. Dtsch Med Wochenschr 3 829- 83, 1905.)...

Figure 5-11. A Relationship between the output of histamine in gastric juice and the volume of gastric juice secreted by Pavlov pouches of dogs during successive half-hour periods after a meal of meat. B Relationship between output of histamine and output of acid secreted by Pavlov pouches of dogs in successive half-hour periods after a meal of meat. (From Code CF, Histamine and gastric secretion, in Wolsten-holme GEW, O Connor CM, eds Histamine. London Ciba Foundation, 1956. Reproduced by permission of the Ciba Foundation.)...

When the Mayo Clinic biochemists improved their methods so that they could separate the two compounds, they found, as before, that 1,4-methyl histamine predominates in the gastric mucosa, but they found that A -dimethyl histamine is the major metabolite of histamine in gastric juice (Table 5-2). Three years later. Code found that all histamine metabolites were present in the gastric juice secreted by a completely isolated, perfused canine stomach in the same proportions his colleagues had previously found in gastric juice of intact animals. Therefore, N-meth-ylated histamine is produced in the stomach itself. " ... 

In quantitative evaluation of acid secretion, total acid output is the product of the [H"] (millimoles per liter) and the volume of gastric juice secreted (milliliters... 

Histamine Histidine Local tissue hormone, reduces blood pressure, effect on gastric Juice secretion, participation in anaphylactic shock and allergic reactions... 

Fluid secreted by the stomach containing hydrochloric acid, digestive enzymes (for example pepsinogen) and intrinsic factor which is necessary for vitamin B 2 absorption. Gastric juice secretion is stimulated by gastrin and also by the vagus nerve which responds to the stimulus of food. 

In this context it is worth mentioning that rabbits seem to be the only species studied where efficient gastric acid inhibition has a significant clinical effect. Oral doses exceeding 80 )imol/kg and above causes decreased food and water intake after only a few days of treatment. These effects were associated with severe constipation. In this species gastric juice secretion, volume as well as acidity probably play an important role for the digestive function. 

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