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Biomedical subjects

N Mascolo

Publications and source records attributed to N Mascolo.

At least 73 records · Page 4Linked to original sources
PubMed1989

Castor oil increases intestinal formation of platelet-activating factor and acid phosphatase release in the rat.

1. When castor oil was administered by gavage to rats, the duodenum and jejunum but not ileum and colon produced large amounts (5-6 fold greater than control) of platelet activating factor (Paf). 2. Intraluminal release of acid phosphatase (AP) was also markedly increased (5-6 fold greater than control) in the duodenum and jejunum of castor oil-treated rats and there was a correlation between the elevated release of AP and intestinal hyperaemia. 3. These findings support a role for Paf as a mediator of intestinal damage induced by castor oil.

Acid Phosphatase↗
PubMed1988

Potentiation by phenolphthalein of the responses of guinea-pig ileum and rat stomach strip to PGE2 and other agonists.

Phenolphthalein was examined for its effect on the activity of isolated muscle (guinea-pig ileum and colon, rat stomach), and on the tissue responses to PGE2, histamine and 5-HT. The ileal circular muscle and both muscle layers of the colon were unaffected by phenolphthalein. In contrast, the laxative potentiated the responses of the longitudinal muscle of guinea-pig isolated ileum and the rat stomach strip to the agonists, particularly PGE2. This potentiation was reduced by indomethacin in vivo, but mepyramine or methysergide had little or no effect. Augmentation of muscle activity by phenolphthalein, particularly in the response to PGE2, may contribute to the laxative effect.

Animals↗
PubMed1988

Flavonoids, leucocyte migration and eicosanoids.

Quercetin reduced the concentration of prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) in the pleural exudate induced in rats by 1% carrageenan given intrapleurally. Leucocyte migration in the exudate was also reduced by the flavonoid. Inhibition of eicosanoids and leucocytes in the exudate was dose-related. Quercetin also reduced LTB4 synthesis in cells stimulated with ionophore A23187, either ex-vivo or in-vitro. A similar, though less active, mode of action was found with quercitrin, while apigenin and luteolin reduced leucocyte accumulation and PGE2 formation, but not LTB4-formation.

Animals↗
PubMed1988

Senna still causes laxation in rats maintained on a diet deficient in essential fatty acids.

The laxative effect of senna has been investigated in normal and essential fatty acid deficient (EFAD) rats. Oral administration of senna pod extract (7-5-90 mg kg-1) produced a dose-dependent increase in the number of soft faeces excreted by normal rats. Senna 30 mg kg-1 also reversed net absorption of water and increased the prostaglandin (PG) production in the colonic lumen of normal rats by about four times. Oral administration of senna pod extract to rats, maintained on a fat-free diet for 30-90 days, produced diarrhoea and reversed net absorption of water as in normal rats. However, a fat-free diet reduced the PG production drastically in the colonic lumen both in senna-free rats and in senna-treated rats. In EFAD rats carrageenan oedema, but not dextran oedema, was also drastically reduced. Since PG mediation is not present in EFAD rats we conclude that the PG are not essential for laxation induced by senna and that water secretion and PG production in the rat intestinal lumen are unrelated.

Animals↗
PubMed1988

Evidence against a dependence of the senna effect on prostaglandin formation.

The laxation induced by senna is not modified in rats either maintained on a diet deficient in essential fatty acids (EFAD) or exposed to cold (6 degrees C) or with yeast-induced fever. In light of our findings it appears conceivable that non-PG-mediated mechanism(s) play a relevant role in laxation induced by senna.

Animals↗
PubMed1987

Effect of cholera toxin on the production of eicosanoids by rat jejunum.

1 Cholera toxin injected i.v. into rats stimulated the production of prostaglandin E2 (PGE2), leukotriene B4 (LTB4) and LTC4 by segments of jejunum, but it had no effect when added to the tissue in vitro. 2 Pretreatment of the animals with the compound BW 755C reduced the increased production of PGE2, LTB4 and LTC4 by i.v. cholera toxin. Pretreatment with indomethacin reduced the production of PGE2. 3 These findings are consistent with the hypothesis that arachidonate metabolites are involved in the diarrhoea induced by cholera toxin.

4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyraz↗
PubMed1987

Laxative drugs.

Explore the source record for details and available documents.

Animals↗
PubMed1986

Laxatives and the production of autacoids by rat colon.

The effects of some laxatives were examined on the formation of histamine, 5-hydroxytryptamine (5-HT) and prostaglandin-like material (PG-LM) by rat intestine in-vitro. Castor oil, senna, sulphosuccinate and bisacodyl, but not mannitol or lactulose, in doses that cause laxation, increased the formation of histamine, 5-HT and PG-LM. Indomethacin or hydrocortisone reduced the increase of PG-LM formation. The data support the idea that the laxative effects of these intestinal secretagogues are due to increased intestinal production of PG-LM, histamine and 5-HT.

Animals↗
PubMed1984

Antipyretic and antibacterial actions of Teucrium polium (L.).

The antipyretic and antibacterial activities of the ethanolic extract of the flowering tops of Teucrium polium (L.) were been studied. The extract was effective against both yeast and carrageenin pyrexia in rats. It also exhibited a marked antibacterial action against both gram positive and gram negative organisms and was found to be non toxic in acute studies.

Animals↗
PubMed1984

Phenolphthalein stimulates the formation of histamine, 5-hydroxytryptamine and prostaglandin-like material by rat jejunum, ileum and colon.

The effects of phenolphthalein on the formation of histamine, 5-hydroxytryptamine(5-HT) and prostaglandin-like material by rat intestine were examined in vivo. Phenolphthalein, in a dose that causes laxation increased the formation of histamine, 5-HT and prostaglandin-like material, and indomethacin reduced these increases. The data support the idea that the laxative effect of phenolphthalein is due to increased intestinal production of prostaglandin, histamine and 5-HT.

Animals↗
PubMed1984

Influence of ricinoleic acid on the contractions elicited by PGE2 on the guinea-pig ileum.

The effect of ricinoleic acid on prostaglandin E2 (PGE2)-evoked contractions was studied on guinea-pig isolated ileum. Addition of ricinoleic acid (10 micrograms ml-1) to the organ bath increased the amplitude of the PGE2-evoked responses. Ricinoleic acid (10 micrograms ml-1) also sensitized the guinea-pig isolated ileum to acetylcholine and histamine. The effect of the ricinoleic acid was greatly reduced by indomethacin either in-vivo (10 mg ml-1) or in-vitro (2 micrograms ml-1).

Animals↗
PubMed1984

Suppression of laxative action of phenolphthalein by orally-administered indomethacin or aspirin.

Oral administration of phenolphthalein produced a dose-dependent increase of wet faeces excreted by mice. The response to phenolphthalein was reduced by pretreatment with indomethacin, aspirin or polyphloretin phosphate (PPP), but not with benoxaprofen. These findings support the view that the effect of phenolphthalein may be suppressed by PG synthetase inhibitors (indomethacin, aspirin) and by PPP.

Administration, Oral↗
PubMed1983

Phytotherapeutic profile of some plants used in folk medicine.

The effect of nine vegetable extracts was evaluated on the carrageenin-induced oedema in the rat. Our results show that the above extracts are able to exert - at different degree - a very marked decrease of the inflammed site related to the presence in the considered plants of several active biologically compounds as sterols and flavonoids. Preliminary chemical analysis of these vegetables are also reported.

Animals↗
PubMed1983

Effect of indomethacin on aloin and 1,8 dioxianthraquinone-induced production of prostaglandins in rat isolated colon.

The effect of aloin and 1,8 dioxyanthraquinone on the release of prostaglandin-like material (PG) from rat isolated colon has been investigated. Orally administered aloin and 1,8 dioxyanthraquinone stimulates PG production by subsequently isolated segments of colon. Indomethacin was able to prevent this increased production of PG. These results suggest that the laxative properties of aloin and 1,8 dioxyanthraquinone may depend, at least in part, on increased prostaglandin synthesis by the intestinal tissue.

Administration, Oral↗
PubMed1982

Enhancement by levamisole of the contractions induced by prostaglandin E2 in the guinea-pig isolated ileum.

The effect of levamisole on prostaglandin E2 (PGE2)-evoked contractions was studied on guinea-pig isolated ileum. Addition of levamisole (10 micrograms/ml) to the organ bath produced a pronounced increase in the amplitude of the PGE2-evoked responses. Levamisole (10 micrograms/ml) also sensitized the guinea-pig isolated ileum to 5-hydroxytryptamine and bradykinin, but not to histamine. The effect of the levamisole was not due to stimulation of autonomic ganglia or cholinergic activity since it was unaffected by hexamethonium or atropine, but it was prevented by indomethacin.

Animals↗