1
|
Ootsubo C, Okumura T, Takahashi N, Wakebe H, Imagawa K, Kikuchi M, Kohgo Y. Helicobacter pylori lipopolysaccharide inhibits acid secretion in pylorus-ligated conscious rats. Biochem Biophys Res Commun 1997; 236:532-7. [PMID: 9240475 DOI: 10.1006/bbrc.1997.6999] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To examine the effect of Helicobacter pylori lipopolysaccharide on gastric secretion, the present study was carried out using pylorus ligated conscious rats. Intraperitoneal administration of Helicobacter pylori lipopolysaccharide significantly inhibited gastric acid secretion (4 hr) in a dose-dependent manner (0.033-1.0 mg/rat). The Helicobacter pylori lipopolysaccharide (1 mg/rat)-induced acid inhibition was still observed 8 hr after injection. Gastric acid secretion (4 hr) was compared in the rats that had received intraperitoneal administration of 1 mg/rat dose of Helicobacter pylori lipopolysaccharide or saline alone 24 hr before. There was no significant difference in gastric acid secretion between the saline- and H. pylori lipopolysaccharide-treated rats. These results suggest for the first time that H. pylori lipopolysaccharide may inhibit acid production, and this acid inhibition may be long-lasting. It is also demonstrated that this anti-secretory action of H. pylori lipopolysaccharide has a reversible effect on gastric secretion. All these results suggest that H. pylori lipopolysaccharide might be involved in the low acid secretory function seen in patients with acute H. pylori infection.
Collapse
Affiliation(s)
- C Ootsubo
- Third Department of Internal Medicine, Asahikawa Medical College, Hokkaido, Japan
| | | | | | | | | | | | | |
Collapse
|
2
|
Saperas E, Taché Y. Interleukin-1 receptor antagonist does not prevent endotoxin-induced inhibition of gastric acid secretion in rats. Dig Dis Sci 1994; 39:152-6. [PMID: 8281850 DOI: 10.1007/bf02090075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The underlying mechanisms involved in endotoxin-induced inhibition of gastric acid secretion were investigated in conscious rats with pylorus ligation for 2 hr. Intraperitoneal injection of endotoxin (0.1, 1, and 5 micrograms/rat) inhibited gastric acid output by 31%, 80%, and 84% respectively. Intraperitoneal endotoxin (1 microgram/rat) -induced inhibition of gastric acid secretion was not altered by pretreatment with the interleukin-1 receptor antagonist, IL-1RA, indomethacin, naloxone, or capsaicin. Treatments were injected peripherally at doses previously shown to antagonize the antisecretory effect of exogenous interleukin-1 beta, to inhibit prostaglandin synthesis in the stomach and brain, to block opiate receptors, and to alter functioning of unmyelinated afferent nerve fibers. These results indicate that the antisecretory effect of endotoxin can be expressed by factors other than interleukin-1, prostaglandins, or opioid peptides that do not require the integrity of capsaicin-sensitive afferent pathways.
Collapse
Affiliation(s)
- E Saperas
- CURE/Digestive Disease Center, VA Wadsworth Medical Center, Los Angeles, California 90073
| | | |
Collapse
|
3
|
Affiliation(s)
- A Uehara
- Department of Internal Medicine (III), Asahikawa Medical College, Hokkaido, Japan
| | | |
Collapse
|
4
|
Taché Y, Saperas E. Potent inhibition of gastric acid secretion and ulcer formation by centrally and peripherally administered interleukin-1. Ann N Y Acad Sci 1992; 664:353-68. [PMID: 1456663 DOI: 10.1111/j.1749-6632.1992.tb39774.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
IL-1 beta is one of the most potent centrally acting inhibitors of gastric acid secretion in rats. Sites of action have been located in the anterior/preoptic area and paraventricular nucleus of the hypothalamus where other biological activities of IL-1 have also been described. IL-1 beta action is, so far, quite unique to this cytokine and its action is not reproduced by IL-2 or TNF alpha. The IL-1 effect involves prostaglandin pathways and is unrelated to CRF. Similarly, systemic injection of IL-1 induces a long lasting inhibition of acid secretion through prostaglandin-dependent mechanisms. Several findings support the possibility that the effect of systemic IL-1 can be CNS-mediated and/or exerted at the periphery through local release of PG in the stomach. Exogenous IL-1 given into either the circulation or the cerebrospinal fluid also inhibits gastric injury induced by a variety of experimental models (stress, aspirin, ethanol). Such a protective effect is mediated through the inhibition of acid secretion and prostaglandin release, although other mechanisms may also contribute. Whether endogenously released IL-1 beta exerts a protective role in the gastric mucosa is still to be investigated.
Collapse
Affiliation(s)
- Y Taché
- Center for Ulcer Research and Education, Veterans Administration Medical Center, Los Angeles, California 90073
| | | |
Collapse
|
5
|
Uehara A, Okumura T, Tsuji K, Taniguchi Y, Kitamori S, Takasugi Y, Namiki M. Evidence that gastric antisecretory action of lipopolysaccharide is not due to a toxic effect on gastric parietal cells. Dig Dis Sci 1992; 37:1039-44. [PMID: 1618051 DOI: 10.1007/bf01300284] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have recently found that bacterial lipopolysaccharide (LPS) or endotoxin at minute doses inhibits the secretion of gastric acid and pepsin in rats. The present study was performed to determine whether this antisecretory action of LPS was a reversible biological response or a result of the destruction of gastric parietal cells by endotoxin. The intraperitoneal injection of LPS into pylorus-ligated rats resulted in a dose-related (40-4000 ng/kg) decrease in gastric acid secretion, with maximal inhibition being observed at a dose of 4000 ng/kg. The stomach then was examined both macroscopically and microscopically for the presence or absence of mucosal lesions or damaged gastric parietal cells. No morphological changes in the gastric mucosal structure including parietal cells were observed even in the rats injected with 4000 ng/kg of LPS. Next, basal gastric acid output was compared in the rats that had received LPS (4000 ng/kg, intraperitoneal) or saline alone 24 hr before. There was no significant difference in gastric acid secretion between the saline- and LPS-pretreated groups, indicating that the secretory capacity of gastric parietal cells returned to the control level at 24 hr after the injection of a maximal antisecretory dose of LPS. These results clearly suggest that the LPS-induced inhibition of gastric secretion results not from its toxic or destructive effect on the gastric secretory mechanism but from its reversible biological effect on gastric physiology.
Collapse
Affiliation(s)
- A Uehara
- Department of Internal Medicine (III), Asahikawa Medical College, Hokkaido, Japan
| | | | | | | | | | | | | |
Collapse
|
6
|
Saperas E, Cominelli F, Taché Y. Potent inhibition of gastric acid secretion by intravenous interleukin-1 beta and -1 alpha in rats. Peptides 1992; 13:221-6. [PMID: 1409001 DOI: 10.1016/0196-9781(92)90100-h] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The influence of human and rat recombinant interleukin-1 (hIL-1 beta and -1 alpha and rIL-1 beta) on acid secretion was investigated in conscious pylorus-ligated rats. Intravenous injection of either hIL-1 beta, hIL-1 alpha or rIL-1 beta dose dependently inhibited gastric acid output with an ED50 of 0.05 microgram, 0.5 microgram and 2.2 micrograms, respectively. The antisecretory action of IL-1 beta was associated with an increase in circulating levels of gastrin. hIL-1 beta-induced inhibition of acid secretion was dose dependently reversed by peripheral injection of the IL-1 receptor antagonist, IL-RA, with a dose ratio of 1:10(3) for complete reversal. The inhibitory effect of hIL-1 beta was blocked by indomethacin and was not modified by IV injections of the CRF receptor antagonist, alpha-helical CRF(9-41), or the monoclonal somatostatin antibody CURE.S6, or by systemic capsaicin pretreatment. These results show that systemic hIL-1 beta-induced inhibition of gastric acid secretion is mediated through IL-1 receptors and prostaglandin pathways, and does not involves CRF receptors, afferent fibers, or changes in circulating gastrin or somatostatin levels.
Collapse
Affiliation(s)
- E Saperas
- Center for Ulcer Research and Education, VA Wadsworth Medical Center, Los Angeles, CA 90073
| | | | | |
Collapse
|
7
|
Tsuji K, Uehara A, Okumura T, Taniguchi Y, Kitamori S, Takasugi Y, Namiki M. The gastric antisecretory action of lipopolysaccharide is blocked by indomethacin. Eur J Pharmacol 1992; 210:213-5. [PMID: 1601059 DOI: 10.1016/0014-2999(92)90674-s] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have recently found that bacterial lipopolysaccharide (LPS) at minute doses inhibits the secretion of gastric acid and pepsin in rats. The present study was performed to examine the mechanism by which LPS exerts its antisecretory action. The i.p. injection of LPS resulted in a dose-dependent (40-4000 ng/kg) decrease in gastric acid output in pylorus-ligated rats. However, preinjection of indomethacin (2-10 mg/kg s.c.), an inhibitor of prostaglandin biosynthesis, prevented the LPS-induced inhibition of gastric secretion in a dose-related manner, while these concentrations of indomethacin by themselves did not affect gastric acid output. These results suggest that LPS requires an intact prostaglandin system to exhibit its inhibitory action on gastric secretion.
Collapse
Affiliation(s)
- K Tsuji
- Department of Internal Medicine, Asahikawa Medical College, Hokkaido, Japan
| | | | | | | | | | | | | |
Collapse
|
8
|
Barocelli E, Impicciatore M, Seaton J, Conter R, Kauffman G. Localization of central prostaglandin E2 antisecretory effects. Gastroenterology 1991; 100:320-7. [PMID: 1985030 DOI: 10.1016/0016-5085(91)90198-t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Intracerebroventricular prostaglandin E2 (PGE2) inhibits stimulated gastric acid secretion; however, the central site of action is unknown. Specific PGE2 binding sites have been localized to the ventromedial hypothalamic nucleus and central amygdala (A). The nuclear accumbens has been shown to play a role in central neurotensin-induced antisecretory effects. These studies tested the hypothesis that microinjections of PGE2 into the ventromedial hypothalamic nucleus, central amygdala, and nuclear accumbens inhibit stimulated gastric acid secretion. The hippocampus served as a cerebral control region. Two days before the experiments, metal cannulas were stereotaxically positioned bilaterally into specific areas of the brain, and metal gastric cannulas were operatively implanted, under nembutal anesthesia, in male 250-g Sprague-Dawley rats. On the experimental day, the rats, fasted for 14 hours, were given saline or PGE2 (0.1-1.0 micrograms in 0.2 microL/side) through the central cannulas 10 minutes before administering pentagastrin (40 micrograms/kg SC). Gastric secretion was measured at 30-minute intervals and expressed as acid output, micromoles per hour. Acid output (mean +/- SE) in control animals was 161 +/- 14 mumol/h. Prostaglandin E2 administration at doses of 0.10, 0.50, and 1.0 micrograms/side (a) into ventromedial hypothalamic nucleus reduced acid output to 53 +/- 11,* 36 +/- 10,* and 27 +/- 11* mumol/h regularly; (b) into NACB reduced acid output to 157 +/- 36, 60 +/- 12,* and 38 +/- 12* mumol/h; and (c) into A reduced acid output to 144 +/- 31, 141 +/- 26, and 90 +/- 19* mumol/h, respectively (*P less than 0.05 by Neuman-Keuls test). Prostaglandin E2 (0.50 micrograms/side) administration into hippocampus had no significant effect on acid output (134 +/- 28 mumol/h). Although central PGE2 administration was associated with hyperthermia, this occurred at lower doses than those required to inhibit acid secretion. Prostaglandin E2 administration into specific brain areas known to have PGE2 receptors, the central amygdala and ventromedial hypothalamic nucleus, and into nuclear accumbens inhibits stimulated gastric acid secretion. These observations suggest that PGE2 may have a physiological role in the central control of gastric acid secretion.
Collapse
Affiliation(s)
- E Barocelli
- Division of General Surgery, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey
| | | | | | | | | |
Collapse
|
9
|
Saperas ES, Yang H, Rivier C, Taché Y. Central action of recombinant interleukin-1 to inhibit acid secretion in rats. Gastroenterology 1990; 99:1599-606. [PMID: 2121579 DOI: 10.1016/0016-5085(90)90463-b] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The influence of recombinant human interleukins-1 beta and -1 alpha and rat interleukin-1 beta on gastric acid secretion was investigated in awake rats with pylorus ligation. IC injection of either human interleukin-1 beta, human interleukin-1 alpha, or rat interleukin-1 beta induced a dose-dependent inhibition of gastric acid output. At IC doses less than 100 ng, human interleukin-1 beta was more effective than the other forms or sources of interleukin-1, whereas at higher doses (100-500 ng), human interleukins-1 beta and -1 alpha and rat interleukin-1 beta were equipotent. The inhibitory effect was observed 30 minutes after interleukin-1 injection and maintained throughout the 6-hour experimental period. IC injection of interleukin-1 beta inhibited vagally stimulated gastric acid secretion induced by IC injection of the stable thyrotropin-releasing hormone analogue RX 77368. Indomethacin (1, 5, and 10 mg/kg, IP, -30 minutes) induced a dose-related prevention of the inhibitory effect of IC interleukin-1 beta. IC injection of the corticotropin-releasing factor antagonist alpha-CRF9-41, bilateral adrenalectomy, and noradrenergic blockade with bretylium did not influence the antisecretory effect of interleukin-1. Polypeptide action was not related to changes in circulating gastrin levels. Human interleukin-1 beta injected IV also inhibited gastric acid secretion, but the peripheral dose required to induce a significant effect was 10(3)-fold higher than when given centrally. These results show that IC interleukin-1 beta acts centrally to induce a long-lasting inhibition of gastric acid secretion, and this effect requires the integrity of prostaglandin pathways. These data suggest a possible interaction between the immune and gastrointestinal systems.
Collapse
Affiliation(s)
- E S Saperas
- Center for Ulcer Research and Education, VA Wadsworth Medical Center, Los Angeles
| | | | | | | |
Collapse
|
10
|
Modlin IM, Basson MD, Adrian TE, Sussman J. Pepsinogen release and acid secretion from human and guinea pig gastric mucosa compromised by hypoxia, endotoxin, or critical illness. Scand J Gastroenterol 1990; 25:865-75. [PMID: 2218392 DOI: 10.3109/00365529008997606] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Despite blockade and neutralization of gastric acid, acute gastric lesions cause substantial morbidity and mortality in critically ill patients. Pepsinogen release in response to noxious stimuli such as hypoxia and endotoxin might contribute to mucosal damage. Guinea pig fundic mucosa was mounted in Ussing chambers. Acid secretion, pepsinogen release, potential difference (PD), and resistance were monitored. Gassing with room air or nitrogen diminished acid secretion and PD but increased pepsinogen release 9.7- and 15.5-fold, respectively (both p less than 0.001). Similarly, endotoxin (0.01 and 0.1 units/ml) dose-dependently inhibited acid secretion and PD but increased pepsinogen release 3.3- and 6.1-fold (both p less than 0.05). Endotoxic and air-gassed tissues were edematous with scattered cellular damage by light and transmission electron microscopy; nitrogen-exposed membranes appeared necrotic. Pepsin release may therefore have resulted from cell damage rather than exocytosis. Intragastric peptic activity in critically ill H2-receptor-blocked patients (n = 20) was 5490 +/- 1701 U/ml. The gastric juice of H2-blocked convalescing surgical patients (n = 20) contained 315 +/- 101 U/ml (p less than 0.0001). Occult blood correlated with intragastric peptic activity (r = 0.59, p less than 0.0001) but not with gastric pH (r = 0.04, p = 0.6). These data suggest that the complex of pathophysiologic abnormalities common in critical illness causes substantial pepsin release. Efflux of this potent mucolytic barrier breaker may damage gastric mucosa in severely stressed patients.
Collapse
Affiliation(s)
- I M Modlin
- Dept. of Surgery, Yale University School of Medicine, New Haven, CT 06510
| | | | | | | |
Collapse
|
11
|
Affiliation(s)
- S R Bloom
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London
| | | |
Collapse
|
12
|
Mutt V. Chemistry of the gastrointestinal hormones and hormone-like peptides and a sketch of their physiology and pharmacology. VITAMINS AND HORMONES 1982; 39:231-427. [PMID: 6755887 DOI: 10.1016/s0083-6729(08)61138-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|