OCCURRENCE OF PROSTAGLANDIN E 2 IN THE HUMAN STOMACH, AND A STUDY OF ITS EFFECTS ON HUMAN ISOLATED GASTRIC MUSCLE

Eley

Scholes

1968

Self Cite

. Prostaglandins E1 and E2 affected intestinal activity both in vitro and in vivo. . Serosal application of prostaglandin to guinea‐pig isolated ileum stimulated the longitudinal muscle but reduced peristaltic contractions of the circular muscle and the propulsion of fluid through the gut. Intraluminal application had little effect. . Injection of prostaglandin into the bloodstream of anaesthetized rats stimulated the longitudinal muscle of the ileum and increased the intraluminal pressure. A similar response sometimes occurred in the guinea‐pig, but in general the effect was variable. . Release of prostaglandin in the gut wall, but probably not into the blood or into the lumen of the gut, may play a part in controlling intestinal motility.

Section: Discussionmentioning

confidence: 96%

Effect of prostaglandins E₁ and E₂ on intestinal motility in the guinea‐pig and rat

Eley

Scholes

1968

Self Cite

“…In general, the longitudinal muscle was stimulated to contract whereas the circular muscle was inhibited, thus following the pattern first seen in the body of the human stomach (Bennett, Murray & Wyllie, 1968). The longitudinal muscle from different regions of the rat small intestine, however, appears to vary in its response to E-type prostaglandin: the duodenum relaxes (Khairallah, Page & Turker, 1967), the jejunum contracts but sometimes first relaxes (Berkstrom et al, 1959), whereas in the present experiments the contraction of the ileum was preceded by a relaxation in only one experiment.…”

Section: Discussionmentioning

confidence: 99%

“…Both the circular and the longitudinal muscle layers of the human and the rat small intestine are less sensitive than those of the guinea-pig, and they are also less sensitive than the human and rat isolated stomach (Bennett, Murray & Wyllie, 1968;Bennett, Friedmann & Vane, 1967). These regional differences may occur because the stomach and ileum arise from embryologically different parts of the gut; both quantitative and qualitative variations in the response of the two regions are found with other naturally occurring substances such as acetylcholine, histamine, 5-hydroxytryptamine and gastrin (Bennett, 1965;Bennett & Whitney, 1966a, b;Bennett, Misiewicz & Waller, 1967).…”

Section: Discussionmentioning

confidence: 99%

“…Prostaglandins have been found in the gastrointestinal wall of man and other animals (Ambache, Brummer, Rose & Whiting, 1966;Vogt, Suzuki & Babilli, 1966;Coceani, Pace-Asciak, Volta & Wolfe, 1967;Bennett, Friedmann & Vane, 1967;Bennett, Murray & Wyllie, 1968), and are released from the serosal and mucosal surface of the rat isolated stomach during peristalsis elicited by electrical stimulation (Coceani et al, 1967;Bennett, Friedmann & Vane, 1967). The longitudinal gastrointestinal muscle of manv species responds with contraction to low concentrations of prostaglandins, but in contrast the circular muscle of the human stomach is inhibited (Bergstrom, Eliasson, Euler & Sjovall, 1959;Horton & Main, 1963;Bennett, Murray & Wyllie, 1948).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of prostaglandins E₁ and E₂ on human, guinea‐pig and rat isolated small intestine

Eley

Scholes

1968

Self Cite

126

. Prostaglandins E1 and E2 contracted the longitudinal muscle of human, guinea‐pig and rat isolated ileum. . The site of action varied with the species. In the rat and in some strips of human tissue prostaglandin appeared to have only a direct action on or in the muscle cells. In the other strips of human tissue and in guinea‐pig ileum the prostaglandins seemed to stimulate both the intrinsic cholinergic nerves and the muscle cells. . In contrast to the longitudinal muscle, the circular muscle of human, guinea‐pig and rat isolated ileum was usually inhibited by prostaglandin, apparently by an action directly on the muscle cells. . Prostaglandins may play a part in the control of intestinal motility.

“…Of all the prostanoids tested only PGI2 consistently relaxed the longitudinal muscle of human stomach or colon, although with PGE, a relaxation sometimes preceded the contraction (Oasti, Omuro, Toyosaka, Kuwata, Miyomoto & Okamoto, 1973), and PGE2 sometimes inhibited ACh-induced contractions (Bennett et al, 1968;Crofts, Stockley & Johnson, 1979). In addition to causing relaxation, PGI2 1 pg/ml reduced contractions of the stomach longitudinal muscle to PGE2 or PGF2, with little effect on U-46619 or ACh.…”

Section: Discussionmentioning

confidence: 99%

Metabolites of Arachidonic Acid Formed by Human Gastrointestinal Tissues and Their Actions on the Muscle Layers

Hensby²,

Sanger

et al. 1981

Self Cite

104

1 Gas chromatography-mass spectrometry demonstrated the presence of arachidonic acid (AA), 6-keto-prostaglandin Fl, and thromboxane B2 (TxB2) in all extracts of homogenized muscle or mucosa from human stomach, terminal ileum or sigmoid colon. Prostaglandin D2 (PGD2), PGE2 or PGF2. were usually found more often in the mucosal extracts. The 12-hydroxy-derivative of AA (12-HETE) was detected in all extracts of the colon but in only some of the other tissues. 2 Most prostanoids tested contracted the longitudinal muscle, the order of potency being U-466 19(an epoxymethano analogue of PGH2)>PGE2>PGF2,,>PGD2; PG12 usually caused relaxation, whereas its breakdown products or TxB2 had weak and variable effects.3 U-46619 or, less potently, PGF2a contracted the circular muscle, whereas PGI2 and usually PGE2 caused relaxation. PGD2, 6-keto-PGF1,,, 6,15-diketo-PGFir. or TxB2 usually had little or no effect.4 PGI2 antagonized contractions to some excitatory prostanoids, without greatly affecting contractions to acetylcholine. 5 For both muscle layers there was a gradient in sensitivity to prostanoids along the gastrointestinal tract. The sensitivities were stomach> distal ileum>sigmoid colon. 6 The results are discussed in relation to gastrointestinal physiology and pathophysiology.