Emptying of stomach

Neurotensin Inhibits emptying of stomach and acid secretion. 

Whereas solid food delays stomach emptying, liquids tend to accelerate the process. Acceleration results from activation of stretch receptors in the stomach wall. When the fluid is water, activation of the inhibitory receptors is stopped. This results in rapid emptying of stomach contents into the duodenum. 

The design of a proper delivery system requires a knowledge of the G.I.tract (i). The nature of the gastric acidic and enzymatic medium has been elucidated. More recently Davis (2) and Harris (3) have studied the rate of emptying of the stomach. Dressman (4) has clinically followed pH variations in both the empty stomach and after a meal finding that sinusoidal pH reductions occur during mastication of solid food, whereas the duodenum maintains a relatively constant pH during introduction of the chyme. 

The most important factors that regulate gastric motility and the rate of emptying of the stomach involve the volume and chemical composition of chyme in the duodenum. Receptors in the duodenum are sensitive to ... 

Inter-digestive migrating contraction Time for 50% emptying of the stomach Technetium-99m... 

Kumar D, Ritman EL, Malagelada JR. Three-dimensional imaging of the stomach role of pylorus in the emptying of liquids. Am J Physiol 1987 253 G79-G85. 

Human stomachs vary greatly in size and shape as is seen from Figure 1 which pictures various normal specimens.3 It is evident that some stomachs hold six or eight times as much as others. It is no wonder from this standpoint that our eating "habits" are not all alike. Coupled with the gross differences in stomach sizes and shapes are the well-known wide differences in the emptying time of stomachs as well as other differences which will be mentioned in later discussions (pp. 6567). Clearly, from the anatomical standpoint it is normal for the stomach to have any one of a great variety of shapes and sizes. 

Digestive system g agonists decrease secretion of stomach acid, reduce gastric motility, and prolong gastric emptying. Pancreatic, biliary, and intestinal secretions are reduced. Intestinal transit is also slowed. Peristaltic movements are reduced, but tone is increased, sometimes causing spasm. As a result, constipation is a frequent problem with opioid use. Bile duct pressure is also increased by opioids. 

The most commonly used emetics are ipecac and apo-morphine. Induced emesis is the preferred means of emptying the stomach in awake patients who have ingested a toxic substance or have recently taken a drug overdose. Emesis should not be induced if the patient has central nervous system depression or has ingested certain volatile hydrocarbons and caustic substances. 

Opioids induce an inhibitory effect on gastrointestinal motility and fluid secretion (Kromer, 1990). The effect is peripherally and centrally mediated. The peripheral component is related to p- and K-receptors in intestinal organs, which are densely equipped with opioid receptors. They are located at parasympathic ganglia and inhibit the release of acetylcholine, which stimulates the contraction of smooth muscles. Inhibition of the intestinal fluid secretion is mediated via inhibition of adenylate cyclase. The intestinal effects of opioids extend to all parts of the gut and results in inhibition of stomach emptying and inhibition of secretion and motility of duodenum, jejunum, colon and rectum. 

Emptying of Liquids and Solids from the Fasted Stomach... 

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