Ethanol gastric lesion aggravated by lung injury in rat. Therapy effect of antiulcer agents.

Hemorrhagic mucosal lesions in the stomach in the rat induced by an intragastrical application of 1 ml of 50 or 75% ethanol were aggravated by preceding lung damage provoked by an intratracheal instillation of pyrogen-free saline or HCl (pH 1.75) or 50-h exposure to 100% oxygen. Due to the particular preceding aggravating circumstances, these lesions were taken to be of a special kind, rather than ordinary. So far, it is not known whether and how antiulcer agents may influence these lesions. Rats received an intratracheal (i.t.) HCl instillation [1.5 ml/kg HCl (pH 1.75)] (lung-lesion), and an intragastric instillation of 96% ethanol (gastric lesion; 1 ml/rat, 24 h after i.t. HCl instillation), and were sacrificed 1 h after ethanol. Basically, in lung injured rats, the subsequent ethanol-gastric lesion was markedly aggravated. This aggravation, however, in turn, did not affect the severity of the lung lesions in the further period, at least for a 1-h observation. Taking intratracheal HCl-instillation as time 0, a gastric pentadecapeptide, GEPPPGKPADDAGLV, M.W.1419, coded BPC 157 (PL-10, PLD-116; 10 microg, 10 ng, 10 pg), ranitidine (10 mg), atropine (10 mg), omeprazole (10 mg), were given [/kg, intraperitoneally (i.p.)] (1) once, only prophylactically [as a pre-treatment (at -1 h), or as a co-treatment (at 0)], or only therapeutically (at +18 h or +24 h); (2) repeatedly, combining prophylactic/therapeutic regimens [(-1 h)+(+24 h) or (0)+(+24 h)], or therapeutic/therapeutic regimens [(+18 h)+(+24 h)]. In general, the antiulcer agents did protect against ethanol gastric lesions regardless of the presence of the severe lung injury, in all of the used regimens. Of note, combining their prophylactic and salutary regimens (at -1 h/+24 h, or at 0/+24 h) may increase the antiulcer potential, and the effect that had been not seen already with single application, became prominent after repeated treatment.

Cysteamine-colon and cysteamine-duodenum lesions in rats. Attenuation by gastric pentadecapeptide BPC 157, cimetidine, ranitidine, atropine, omeprazole, sulphasalazine and methylprednisolone.

Recently, we showed cysteamine-duodenal lesions without gastric acid, since they were induced also in gastrectomized rats, as in naive rats, and they were inhibited by the novel stomach pentadecapeptide BPC 157 as well as standard antiulcer drugs (i.e. cimetidine, ranitidine, omeprazole, bromocriptine, atropine). Therefore, as an advantage of considering cysteamine as a directly acting cytotoxic agent and mentioned agents as direct cytoprotective agents, the present focus was on the ulcerogenic effect of cysteamine and protective effect of gastroduodenal antiulcer agents outside upper gastrointestinal tract (i.e. in colon). Intrarectal administration of the cysteamine (200 or 400 mg/kg b.w) produced severe colon lesions (i.e. transmural inflammation with serosal involvement) in rats (30 min-72 h-experimental period), apparently distinctive from smaller lesions after non-specific irritant enema [diluted HCl solution, pH 3.8 (adjusted to pH of cysteamine solution (pH 3.8)]. All of the tested antiulcer agents were applied simultaneously with cysteamine enema (8 cm from the anus, in a volume of the 1.0 ml/rat) intraperitoneally (i.p.), intragastrically (i.g.) or intrarectally (i.r.). Pentadecapeptide BPC 157 (10 microg or 10 ng/kg b.w.), given in either regimen, previously shown to have, besides others, a particular beneficial activity just in the intestinal mucosa, inhibited these cysteamine colon lesions (assessed after 30 min, 60 min, 180 min, 24 h, 48 h, 72 h following cysteamine in a dose of either 200 or 400 mg/kg i.r.). Cysteamine-colon lesions were also attenuated by standard antiulcer agents (mg/kg b.w.), given i.p., i.g., or i.r., such as ranitidine (10), cimetidine (50), omeprazole (10), atropine (10), together with methylprednisolone (1), and sulphasalazine (50, i.r.), assessed 30 min following application of 200 mg of cysteamine. Finally, standard cysteamine duodenal lesions (assessed 24 h after a subcutaneous application of 400 mg/kg of cysteamine) were also attenuated by these agents application (given in the same doses, i.p., 1 h before cysteamine), with only exception to sulphasalazine. Thus, the extended cysteamine specific ulcerogenic effect, cysteamine colon/duodenum lesion-link and an extenuation of agents protection from upper to lower part of gastrointestinal tract (i.e. stomach pentadecapeptide BPC 157, standard antiulcer agents, cimetidine, ranitidine, atropine, omeprazole) and vice versa (remedies for inflammatory bowel disease) evidenced in the present study may be potentially important for both further experimental and clinical research.

Therapy effect of antiulcer agents on new chronic cysteamine colon lesion in rat.

After demonstration that cysteamine induced duodenal lesions in gastrectomized rats, while a number of antiulcer drugs mitigated these lesions, it was shown that one single intrarectal (i.r.) cysteamine application produced severe colon lesions in acute studies in rats. Thus, the further focus was on the protracted effect of cysteamine challenge (400 mg/kg b.w. i.r.) and therapy influence in chronic experiments in female rats. Regularly, cysteamine colon lesions were markedly mitigated by ranitidine (10), omeprazole (10), atropine (10), methylprednisolone (1), sulphasalazine (50; mg/kg), pentadecapeptide BPC 157 (PL-10, PLD-116; 10 microg or 10 ng/kg). Specifically, after 1 or 3 months following initial challenge (cysteamine 400 mg/kg i.r.) in female rat, the therapy [BPC 157 (PL-10, PLD-116 (10.0 microg or 10.0 ng/kg; i.g., i.p., i.r.), ranitidine, omeprazole, atropine, methylprednisolone, sulphasalazine (i.p.)] reversed the protracted cysteamine colon injury: the 1 week-regimen (once daily application) started after 1 month post-cysteamine, as well as the 2 weeks-regimen (once daily application), which started after 3 months. The effect on recidive lesion was also tested. These cysteamine lesions may reappear after stopping therapy (after stopping therapy for 3 weeks at the end of 2-weeks regimen started in 3 months-cysteamine female rats) in sulphasalazine group, while this reappearance is markedly antagonized in pentadecapeptide BPC 157 (PL-10, PLD-116)-rats (cysteamine-colon lesion still substantially low).

Chronic cytoprotection: pentadecapeptide BPC 157, ranitidine and propranolol prevent, attenuate and reverse the gastric lesions appearance in chronic alcohol drinking rats.

Unlike severe gastric damage acutely induced by ethanol administration in rat, the ulcerogenic effect of chronic alcohol administration (3.03 g/kg b.w. or 7.28 g/kg b.w.) given in drinking water, producing liver lesions and portal hypertension, is far less investigated. Therefore, focus was on the antiulcer effect of the gastric pentadecapeptide BPC 157, GEPPPGKPADDAGLV, M.W. 1419, known to have a beneficial effect in variety of gastrointestinal lesions models (10 microg or 10 ng/kg b.w. i.p. or i.g.), ranitidine (10 mg/kg b.w. i.g.) and propranol (10 mg/kg b.w. i.g.) or saline (5 ml/kg b.w. i.p./i.g.; control). They were given once daily (1) throughout 10 days preceding alcohol consumption, (2) since beginning of alcohol drinking till the end of the study, (3) throughout the last month of alcohol consumption, 2 months after alcohol drinking had been initiated. Gastric lesions were assessed, at the end of 3 months drinking [(1), (2)] or with respect to therapeutic effect of medication before medication or at the end of therapy. Pentadecapeptide BPC 157, ranitidine and propranolol may prevent gastric lesion development if given prophylactically, before alcohol drinking. Likewise, they attenuate the lesion appearance given once daily throughout the drinking period. Importantly, when given therapeutically, they may antagonize otherwise pertinent lesion presence in stomach mucosa of the drinking rats. Thus, these results demonstrate that pentadecapeptide BPC 157, ranitidine and propranol may prevent, attenuate or reverse the gastric lesions appearance in chronically alcohol drinking rats, and may be used for further therapy, while the other studies showed that their effect (except to ranitidine) is parallel with their beneficial effect on liver lesion and portal hypertension.