Peristalsis

Canadine is bitter and in small doses causes drowsiness and depression. In large doses it gives rise to transient excitement succeeded by depression and paralysis of the central nervous system. Its injection is followed by violent peristalsis with diarrhoea. It is said to have no effect on the blood pressure. The pharmacological action of canadine a- and -meihochlorides was examined by Laidlaw, who found both to have the curare-like action common to ammonium bases, the -isomeride being the more active the relative activities of the four optically active forms are given as h da. ip dp = 1 Q 2 28. 

A further development of this subject is due to Aeschlimann and Reinert, who found that in the series represented by (XLI) thedimethyl-carbamic ester (XLI R = Me) and the methylphenylcarbamic ester (XLI R = Ph) were at least as active as physostigmine in stimulating peristalsis. The miotic activity of the dimethylcarbamic ester (prostig-mine, neostigmine) is similar to that of physostigmine, that of the methylphenylcarbamic ester being weak. 

As under most circumstances progesterone action will hold primacy over estrogenic effects, the cervical mucus, endometrium, and probably the fallopian tubes reflect progestational stimulation. The cervical mucus becomes thick and viscous and thus impervious to spermatozoa. The endometrium is in a state that is not receptive for implantation of a fertilized egg. Probably, the progestational impact on the secretory activity and peristalsis in the fallopian tubes also assists the general contraceptive effect. It is difficult, however, to assess the relative contribution of the various effects to the... 

Constipation related to slowing of peristalsis in the gastrointestinal tract... 

Antidiarrheals decrease intestinal peristalsis, which is usually increased when the patient has diarrhea. Examples of these drug s include difenoxin with atropine (Motofen), diphenoxylate witii atropine (Lomotil), and loperamide (Imodium). 

Hyperosmolar drugs dehydrate local tissues, which causes irritation and increased peristalsis, with consequent evacuation of the fecal mass. Glycerin is a hyperosmolar drug. 

Irritant or stimulant laxatives increase peristalsis by direct action on the intestine. An example of an irritant laxative is cascara sagrada and senna (Senokot). 

Saline laxatives attract or pull water into the intestine, thereby increasing pressure in the intestine, followed by an increase in peristalsis. Magnesium hydroxide (Milk of Magnesia) is a saline laxative. 

Many patients with GERD produce normal amounts of acid, but the acid produced spends too much time in contact with the esophageal mucosa. The contact time is dependent on the rate at which the esophagus clears the noxious material, as well as the frequency of reflux. The esophagus is cleared by primary peristalsis in response to swallowing, or by secondary... 

The pathophysiology of GERD is a complex process. It is difficult to determine which occurs first gastroesophageal reflux leading to defective peristalsis with delayed clearing, or an incompetent lower esophageal sphincter pressure leading... 

Loperamide stimulates enteric nervous system receptors, inhibiting peristalsis and fluid secretion. It improves stool consistency and reduces the number of stools.21 Consequently, it is most useful in patients who have diarrhea as a prominent symptom. However, it can occasionally aggravate abdominal pain. 

Tegaserod maleate (Zelnorm) stimulates 5-HT4 receptors in the GI tract, thereby increasing intestinal secretion, peristalsis, and small bowel transit. It also reduces sensitivity related to abdominal distention. It has been shown to be more effective than placebo in improving global IBS symptoms and altered bowel habits in constipation-predominant IBS.21 Diarrhea is a possible adverse effect. 

Bile The yellowish-brown or green fluid secreted by the liver and discharged into the duodenum where it aids in the emulsification of fats, increases peristalsis, and retards putrefaction. 

Purgative. Elder increases bile secretions, which causes intestinal peristalsis. Use cautiously as elder leaves can be a very intense way to clean the bowels. Fresh flowers are more purgative than dried ones. Parts used flowers, inner bark, leaves. 

Distinguish between the two types of gastrointestinal motility segmentation and peristalsis... 

The contents of the tract must also be continually moved along so that it can be acted upon by the sequential regions of the tract. Peristalsis is a muscular contraction that produces a ring of contraction that moves along the length of the tract. This wave-like contraction causes propulsion and forces the contents forward. Peristalsis is more important in the esophagus and stomach. 

The ability of such a protein to access the muscularis externa and thereby influence peristalsis in vivo has to be called into question, but a role for regulation of local spasm via inhibition of the muscularis mucosa is feasible. Similarly, a role for parasite AChEs in the latter phenomenon cannot yet be discounted. 

The digestive system of poultry is also basically a tube, beginning at the mouth and ending at the vent (Fig. 13.1). Food is taken in via the mouth and mixed with saliva to lubricate it. The bolus moves down the oesophagus by gravity and a wave-like contraction of the muscles (peristalsis). Then it enters the crop where it is stored if the stomach is full. A certain amount of softening and fermentation may occur here. The crop is situated just outside the entrance of the chest cavity (thoracic inlet) and is an expansion of the oesophagus. 

OBD comprises a constellation of GI symptoms including OIC, incomplete evacuation, inhibition of gut peristalsis, bloating, pain, nausea/ vomiting, and increased gastric reflux and tone of intestinal sphincters [3]. Approximately 40% of patients taking chronic opioids for nonmalig-nant pain develop bowel dysfunction [25]. 

Concurrent colonization by Gram-negative bacilli occurs in some patients with failure of the gastric acid barrier, suggesting additional deficiencies of host defense abnormal oral flora, malnutrition, general illness, or diseases or medication interfering with intestinal peristalsis and clearance. This type of microflora is also seen in 10-30% of patients on acid inhibitors, for which mucosal injury and functional changes related to peptic ulcer and reflux disease may be responsible. 

When intestinal peristalsis and clearance are intact, the bacteria are rapidly transported aborally, and in the mid jejunum bacterial counts are in general low (normal) despite dense gastric colonization. Considerable evidence indicates that bacteria recovered from small bowel under such conditions are transient rather than resident. 

Roily and Liebermeister [95] showed that bacteria introduced into the small bowel disappeared rapidly, without bile, pancreatic, and intestinal juices having antibacterial properties alone or mixed. Later studies, of which those by Dack and Petran [96], Dixon [99] and Dixon and Paulley [100] are of particular importance, provided considerable further evidence that intestinal peristalsis is the main line of defense against bacterial colonization of the small bowel. This was also concluded by Donaldson [101-103] when he reviewed host defense mechanisms in 1964. At that time, however, the insights into small bowel motility were confined to the reflex-mediated peristaltic behavior. 

Intestinal mechanical clearance thus consists of both reflex-mediated contractions (peristalsis) elicited by the stimulatory effect of luminal contents and of periods of spontaneous contractile activity (e.g. the migrating motor complex). During fasting about 50% of intestinal transit has been attributed to phase III of the migrating motor complex, the remaining mostly to the propulsive contractions and motor patterns during phase II [ 108]. Luminal flow can also occur in the absence of propagating contractions of the circular muscle layer, so far considered the motor event mainly responsible for flow in the small intestine. 

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