Castor Oil-induced Diarrhea In Mice Research Articles

Medicinal potential of Passiflora foetida L. plant extracts: biological and pharmacological activities

To investigate analgesic, antidiarrhoeal and cytotoxic activities of the ethanol extract of Passiflora foetida L. (Passifloraceae) by three experimental methods. Analgesic activity of the ethanol extract of Passiflora foetida L. (EEPF) acetic acid-induced writhing inhibition in mice. The method of castor oil-induced diarrhoea in mice was utilized to evaluate antidiarrhoeal activity. The cytotoxic activity of EEPF was explored with a brine shrimp lethality bioassay. The extract showed 68.75% and 30.00% inhibition of writhe at the doses of 500 and 250 mg/kg body weight, respectively. The extract increased the mean latent period prior to diarrhoeal onset to about 1.55 h and 1.17 h, and decreased the mean number of stools to 4.4 and 5.6 at the doses of 500 and 250 mg/kg body weight. The extract also demonstrated cytotoxic activity in the brine shrimp lethality assay, and the median lethal concentration for brine shrimp nauplii was 80 μg/mL. The results suggest that the plant extract has analgesic and antidiarrhoeal activities, supporting its uses in traditional medicine. The results also demonstrate that the plant extract possesses cytotoxic activities.

Pharmacological Activities of Blumea lacera (Burm. f) DC: A Medicinal Plant of Bangladesh

Aims: The crude methanol extract of whole plant of Blumea lacera (Burn.f.) DC. has been investigated for anti-diarrheal, antimicrobial, anxiolytic, anti-atherothrombosis, membrane stabilizing and alpha-amylase inhibitory activities.Place and Duration of Study: The study was carried out in 2013 in the Department of Pharmacy, Southern University Bangladesh, Chittagong, Bangladesh.Methodology: Test for anti-diarrheal activity was carried out by castor oil-induced diarrhea in mice. The preliminary antimicrobial activity was determined by the agar disc diffusion method. The anxiolytic activity was examined in mice by using the hole board test and open field test (OFT). The anti-atherothrombosis activity was evaluated using standard streptokinase. The membrane stabilizing activity was assessed by using hypotonic solution induced hemolysis of human erythrocyte. The plant extract was also assessed for anti-diabetic ability using In vitro α-amylase inhibitory potential. The α-amylase inhibitory activity of B. lacera was measured using the starch-iodine method.Results: The crude extract of B. lacera showed anti-diarrheal activity in dose-dependent manner. In antimicrobial assay, this extract showed better activity against the tested fungi compared to the bacteria used in the screening. Significant anxiolytic activity was found for this plant extract. In the In vitro anti-atherothrombosis test, the extract exhibited 46.17% clot lysis as compared to the standard, streptokinase (81.53%). In membrane stabilizing activity test, the plant extract at 1.0mg/ml inhibited the heat-induced hemolysis of RBCs by 52.27% whereas the standard acetyl salicylic acid (ASA) demonstrated 81.72% inhibition of hemolysis. Our results revealed that the extract had dose dependent prevention of digestion of carbohydrates by inhibiting α-amylase. The ability of B. lacera to inhibit thermal-and hypotonic-enzyme activity was found to be statistically significant (p=0.05).Conclusion: These results demonstrated that B. lacera may be used in pharmaceutical applications because of its effective pharmacological properties.

Antispasmodic and antidiarrheal activities of rhizomes of Polygonatum verticillatum maneuvered predominately through activation of K+ channels

Polygonatum verticillatum has traditionally been used for various purposes. The present study was aimed to validate the antispasmodic and antidiarrheal properties of crude methanolic extract of rhizomes of P. verticillatum (PR). Isolated rabbit jejunum preparations were suspended in tissue baths to measure the isotonic responses using Power Lab data acquisition system for the antispasmodic activity of PR, while the antidiarrheal activity was conducted in vivo in mice. PR caused complete relaxation of the spontaneous contractions of isolated rabbit jejunum preparations in a dose-dependent mode. A complete inhibition was observed against low potassium (K(+); 25 mM)-induced contractions, while the plant extract partially inhibited the high K(+)(80 mM)-induced contractions. From a mechanistic point of view, the spasmolytic effect of PR against low K(+)was antagonized by glibenclamide similar to the effect of cromakalim, thus showing the presence of constituents in PR mediating spasmolytic activity predominantly through the activation of adenosine triphosphate-sensitive K(+)channels. When tested against castor oil-induced diarrhea in mice, oral administration of the plant extract manifested marked antidiarrheal activity at the doses of 500 and 1000 mg/kg similar to loperamide. This study provided a pharmacological basis for the medicinal use of PR in abdominal colic and diarrhea.

Anti-diarrhea and anti-oxidant properties of Magnolol

Purpose: To provide an experimental basis for the anti-diarrheal and anti-oxidant properties of the bark extract of Magnolia officinalis Rehd. et Wils., a Chinese traditional herb called magnolol.Methods: The effects of magnolol on castor oil-induced diarrhea, small intestinal transit (SIT) in mice were investigated. Additionally, the antioxidant activity of magnolol was assessed in mice by the following parameters: glutathione (GSH), total antioxidant capacity (T-AOC), antioxidant enzyme activities and their gene expression level.Results: Compared with diarrhea model control group, magnolol (25, 50, or 100 mg/kg body weight) showed significant (p < 0.05) inhibitory activity against castor oil-induced diarrhea in mice. Administration of magnolol (25, 50, and 100 mg/kg) also lowered neostigmine-induced SIT acceleration to 60.34 ± 5.17, 59.61 ± 7.66, and 54.12 ± 7.27 %, respectively, as against 70.1 ± 6.89 % for neostigmine control group. In vivo antioxidant assay results showed that mice treated with magnololexhibited significantly (p < 0.001) higher activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities in blood, compared to control. Similarly, magnolol proupsshowed significantly higher CAT and SOD and T-AOC activities (p < 0.01) than control in liver tissues. The 100 mg/kg magnolol group had significantly higher liver GSH content than normal control group(1.01 vs. 0.79 mg/mg protein). At 25 and 50 mg/kg doses, magnolol significantly enhanced gene expression levels of CAT (p < 0.01) in liver.Conclusion: Findings from this study indicate that magnolol possesses anti-diarrheal activity and is probably one of the main anti-diarrhea ingredients of Cortex Magnoliae Officinalis. Magnolol modulation of the activity and gene expression of antioxidant enzymes may therefore exert beneficial effects in antioxidant defense.Keywords: Magnolol, Diarrhea, Small intestinal transit, Antioxidant enzyme, Gene expression

Pharmacological basis for the medicinal use of <i>Morus alba</i> in gut and airways disorders

Crude extract of Morus alba at 100 mg/kg exhibited protective effect against castor oil-induced diarrhea in mice. In isolated rabbit jejunum, M. alba (0.3-10 mg/mL) inhibited the spontaneous contractions and caused glibenclamide-sensitive inhibition of low K + (20 mM)-induced contractions, with mild effect on high K + (80 mM). Similarly, cromakalim caused inhibition of low K + , but not of high K + , while verapamil did not differentiate in its inhibitory effect on two concentrations of K + . M. alba (3.0-30 mg/kg) caused suppression of carbachol (100 µg/kg)-induced increase in inspiratory pressure of anaesthetized rats. In guinea-pig trachea, M. alba completely inhibited low K + contractions, with partial effect on high K + . M. alba (0.3-1.0 mg/mL) caused leftward shift of isoprenaline-induced inhibitory concentration response curves, like papaverine. These results indicate that M. alba possesses a combination of K ATP channel opening, weak Ca ++ -antagonist and phosphodiesterase inhibitory mechanisms, which explain its medicinal use in hyperactive gut and airways disorders.

Species Differences in the Antidiarrheal and Antispasmodic Activities of Lepidium sativum and Insight into Underlying Mechanisms

The aim of this study was to see if the crude extract of Lepidium sativum (Ls.Cr) exhibits species specificity in its antidiarrheal and antispasmodic activities along with insight into the underlying mechanisms using the in-vivo and in-vitro experiments. Ls.Cr inhibited castor oil-induced diarrhea in mice at doses (300 and 1000 mg/kg) three times higher dose than for rats. In isolated rat ileum and jejunum, Ls.Cr completely inhibited carbachol (CCh), low K⁺ (25 mM) and high K⁺ (80 mM)-induced contractions, while in guinea-pig tissues, Ls.Cr caused complete inhibition of only CCh-induced contraction. In rabbit tissues, Ls.Cr completely inhibited CCh and low K⁺-induced contractions sensitive to K⁺ channel antagonists. Pretreatment of guinea-pig and rat tissues with Ls.Cr caused a rightward shift in CCh-induced contractions in a pattern similar to dicyclomine, while in rabbit and rat tissues, Ls.Cr shifted isoprenaline curves to the left similar to papaverine. These data indicate that the antidiarrheal and antispasmodic activities of L. sativum are species dependent, mediating its antispasmodic effect through combinations of multiple pathways including activation of K⁺ channels, and inhibition of muscarinic receptors, Ca⁺⁺ channels and PDE enzyme. Rat tissues showed the highest potency. Based on the results, we recommend using multiple species to know the real pharmacological profile of medicinal products.

Gut and airways relaxant effects of Carum roxburghianum

Ethnopharmacological relevanceCarum roxburghianum is traditionally used in hyperactive gastrointestinal and respiratory disorders. The present study was carried out to investigate the possible gut and airways relaxant potential of Carum roxburghianum to rationalize its folk uses. Materials and methodsCrude extract of Carum roxburghianum (Cr.Cr) was studied in in vivo and in vitro techniques. ResultsCr.Cr exhibited protective effect against castor oil-induced diarrhea in mice at 100–1000mg/kg. In rabbit jejunum preparations, Cr.Cr (0.03–3.0mg/mL) caused relaxation of spontaneous and K+ (80mM)-induced contractions at similar concentrations, like papaverine. Pretreatment of tissues with Cr.Cr (0.1–1.0mg/mL) shifted Ca++ concentration–response curves (CRCs) to right, like verapamil. Cr.Cr (0.03 and 0.1mg/mL) caused leftward shift of isoprenaline-induced inhibitory CRCs, similar to papaverine. In isolated guinea-pig ileum, Cr.Cr (0.01 and 0.03mg/mL) produced rightward parallel shift of acetylcholine-curves, like atropine. Cr.Cr (1.0–30mg/kg) caused suppression of carbachol (CCh, 100μg/kg)-induced increase in inspiratory pressure of anaesthetized rats. In guinea-pig trachea, Cr.Cr (0.03–1.0mg/mL) relaxed CCh and high K+-induced contractions, shifted isoprenaline-induced inhibitory CRCs to left at 0.1 and 0.3mg/mL and CCh-curves parallel to right (0.01 and 0.03mg/mL). Cr.Cr did not cause any mortality of mice up to 10g/kg dose. ConclusionThese results indicate that Carum roxburghianum possess combination of antidiarrheal, antispasmodic and bronchodilatory effects, which provides pharmacological basis to its traditional use in the disorders of gut and airways hyperactivity, like diarrhea, colic and asthma.

Pharmacological explanation for the medicinal use of Juniperus excelsa in hyperactive gastrointestinal and respiratory disorders

Crude extract of Juniperus excelsa (JeExt), which tested positive for the presence of anthraquinone, flavonoids, saponins, sterols, terpenes and tannin, exhibited a protective effect against castor oil-induced diarrhoea in mice at 100-1000 mg/kg. In rabbit jejunum preparations, JeExt (0.01-1.0 mg/mL) caused relaxation of spontaneous and K(+) (80 mM)-induced contractions at similar concentrations to papaverine, whereas verapamil was relatively more potent against K(+). JeExt (0.03-0.3 mg/mL) shifted Ca(2+) concentration-response curves to the right, like papaverine or verapamil. JeExt (0.003-0.01 mg/mL) caused a leftward shift of isoprenaline-induced inhibitory concentration-response curves, similar to papaverine. JeExt (1.0-30 mg/kg) caused suppression of carbachol (CCh, 100 μg/kg)-induced increase in inspiratory pressure of anaesthetized rats. In guinea-pig trachea, JeExt (0.001-3.0 mg/mL) relaxed CCh (1 μM)- and high K(+)-induced contractions and shifted isoprenaline-induced inhibitory curves to the left. This study suggests that Juniperus excelsa possibly exhibits a combination of Ca(2+) antagonist and phosphodiesterase inhibitory effects, which provides a pharmacological basis for its traditional use in disorders of gut and airways hyperactivity, such as diarrhoea, colic and asthma.

Antidiarrhoeal and bronchodilatory potential of Valeriana wallichii

This study describes the antidiarrhoeal and bronchodilatory activities of Valeriana wallichii D.C. (Valerianaceae). The crude extract of V. wallichii (Vw.Cr) caused inhibition of castor oil-induced diarrhoea in mice at 300–600 mg kg−1. In guinea-pig trachea, Vw.Cr concentration dependently (0.03–3.0 mg mL−1) relaxed the low K+ (25 mM)-induced contractions, with a mild effect on the contractions induced by high K+ (80 mM). In the presence of glibenclamide, the relaxation of low K+-induced contractions was prevented. Similarly, cromakalim caused glibenclamide-sensitive inhibition of low K+, without any effect on high K+. These results indicate that V. wallichii exhibits antidiarrhoeal and bronchodilatory activities, possibly through K+ channel activation, and thus reveal its medicinal usefulness in hyperactive gut and airway disorders such as diarrhoea and asthma.

Antidiarrheal and antispasmodic activities of Salvia officinalis are mediated through activation of K+ channels

This study was conducted to provide pharmacological basis for the medicinal use of Salvia officinalis in diarrhea. The crude extract of S. officinalis was studied using the in vivo and in vitro assays. The crude extract inhibited castor oil-induced diarrhea in mice at the dose of 100 and 300 mg/kg. In isolated rabbit jejunum, it caused a dose-dependent (0.1-3 mg/mL) relaxation of spontaneous as well as low K+ (25 mM) and high K+ (80 mM)-induced contractions, being distinctly more potent on low K+. Pretreatment of tissue with 4-aminopyridine (1 mM) almost completely blocked the inhibitory effect of crude extract on low K+. These results indicate that the crude extract of S. officinalis possesses antidiarrheal and antispasmodic activities mediated possibly through the dominant activation of voltage-dependent K+ channels and this study provides sound pharmacological basis for its medicinal use in diarrhea and gut spasm.

Antispasmodic and Antidiarrheal Activities of Valeriana hardwickii Wall. Rhizome Are Putatively Mediated through Calcium Channel Blockade

Valeriana hardwickii is indigenous to Pakistan, Burma and Ceylon, where it is traditionally being used as an antispasmodic and antidiarrheal, besides its culinary use as spice. The aim of this paper was to provide pharmacological validation to these medicinal uses. The crude aqueous-methanolic extract of Valeriana hardwickii rhizome (Vh.Cr) was studied on isolated rabbit jejunum and castor oil-induced diarrhea in mice for spasmolytic and antidiarrheal properties, respectively. Vh.Cr caused concentration-dependent (0.01–1 mg/mL) relaxation of spontaneous contractions in isolated rabbit jejunum and inhibited K+-induced contractions (0.01–0.3 mg/mL), similar to verapamil, suggestive of calcium channel blockade (CCB). The CCB effect was confirmed when pretreatment of the jejunum preparations with Vh.Cr produced a concentration-dependent (0.03–0.1 mg/mL) rightward shift in the Ca++ concentration-response curves, as caused by verapamil. Vh.Cr exhibited dose-dependent (100–300 mg/kg) protection against castor oil-induced diarrhea in mice. Loperamide, a standard antidiarrheal drug, similarly prevented the diarrhea. These data indicate the presence of CCB effect in the extract of Valeriana hardwickii rhizome, possibly mediating its antispasmodic and antidiarrheal activities and provide a scientific base for its traditional use in hyperactive gut disorders.

Evaluation of the effects of Olea europaea L. subsp. africana (Mill.) P.S. Green (Oleaceae) leaf methanol extract against castor oil-induced diarrhoea in mice

Olea europaea L. subsp. africana (Mill.) P.S. Green is widely used in South Africa by traditional medicine practitioners to treat diarrhoea. However, little is known scientifically about this South African species in the treatment of diarrhoea. The main aim of the study therefore was to investigate the antidiarrhoeal effect of the leaf methanol extract of the plant species in mice. The antidiarrhoeal activity of the leaf methanol extract of O. europaea subsp. africana was studied using a castor oil-induced diarrhoeal test. The antipropulsive activity of the plant extract was also investigated using the charcoal meal transit test. Standard methods were used to investigate the acute toxicity and effect of O. europaea subsp. africana on castor oil-induced intraluminal fluid accumulation. Leaf methanol extract of O. europaea subsp. africana and loperamide, a standard antidiarrhoeal drug, significantly reduced the number of diarrhoeal episodes induced by castor oil, significantly decreased the stool mass, significantly delayed the onset of the diarrhoea and protected the animals against castor oil-induced diarrhoea. Both O. europaea subsp. africana and loperamide significantly decreased the gastrointestinal transit of charcoal meal and castor oil-induced intraluminal fluid accumulation in mice. The LD50 value was found to be 3475 mg/kg (p.o.). The results obtained suggest that the leaf methanol extract of O. europaea subsp. africana has an antidiarrhoeal property and that, given orally, it may be non-toxic and/or safe in mice.

Antidiarrheal, antisecretory, and bronchodilatory activities of Hypericum perforatum

This study describes the antidiarrheal, antisecretory, and bronchodilatory activities of Hypericum perforatum Linn. (Hypericaceae), commonly known as St. John’s wort, to justify its traditional use in the hyperactivity of the gastrointestinal and respiratory systems. The crude extract of Hypericum perforatum (Hp.Cr) at a dose of 500 mg/kg caused 20% protection against castor oil-induced diarrhea in mice and 60% at 1000 mg/kg (p < 0.05 vs. saline). Hp.Cr at 300 and 1000 mg/kg reduced the castor oil-induced fluid accumulation in mice to 107.0 ± 3.3 g (p < 0.01) and 84.0 ± 4.2 g (p < 0.001) respectively, whereas in the castor oil-treated group, it was 126.9 ± 3.9 g. When tested against carbachol (CCh)-mediated bronchoconstriction in rats under anesthesia, Hp.Cr dose-dependently (3– 30 mg/kg) suppressed the CCh (1 μmol/kg)-induced increase in the inspiratory pressure. Thus this study rationalizes the Hypericum perforatum usefulness in overactive gut and airways disorders, such as diarrhea and asthma.

Antidiarrhoeal and spasmolytic activities of the methanolic crude extract of Alstonia scholaris L. are mediated through calcium channel blockade

This study was aimed to provide a pharmacological basis to the medicinal use of Alstonia scholaris as an antidiarrhoeal and antispasmodic by using in vivo and in vitro techniques. In the in vivo study the crude extract of Alstonia scholaris (As.Cr), which tested positive for the presence of alkaloids, provided 31-84% protection against castor oil-induced diarrhoea in mice at 100-1000 mg/kg doses, similar to loperamide. In isolated rabbit jejunum preparation, the As.Cr caused inhibition of spontaneous and high K(+) (80 mm)-induced contractions, with respective EC(50) values of 1.04 (0.73-1.48) and 1.02 mg/mL (0.56-1.84; 95% CI), thus showing spasmolytic activity mediated possibly through calcium channel blockade (CCB). The CCB activity was further confirmed when pretreatment of the tissue with the As.Cr (0.3-1 mg/mL) caused a rightward shift in the Ca(++) concentration-response curves similar to verapamil, a standard calcium channel blocker. Loperamide also inhibited spontaneous and high K(+) precontractions as well as shifted the Ca(++) CRCs to the right. These results indicate that the crude extract of Alstonia scholaris possesses antidiarrhoeal and spasmolytic effects, mediated possibly through the presence of CCB-like constituent(s) and this study provides a mechanistic base for its medicinal use in diarrhoea and colic.

Insight into the possible mechanism of antidiarrheal and antispasmodic activities of piperine

Piperine is a piperidine-ring containing alkaloid and a major constituent of Piper nigrum Linn. and Piper longum Linn. species, belonging to the Piperaceae family. The present study explored their mode of action in gastrointestinal disorders, such as diarrhea and colic. Piperine at the dose of 10 mg/kg provided complete protection from castor oil-induced diarrhea in mice, similar to that of loperamide. In isolated rabbit jejunum preparations, piperine exhibited concentration-dependent inhibition of spontaneous contractions with an EC50 value of 149.1 μM (89.26–249.20, 95% CI). When used to treat high K+ (80 mM)-induced sustained contractions, piperine inhibited such contractions with an EC50 value of 80.86 μM (56.10–116.50, 95% CI), which suggested a calcium channel blocking (CCB) effect. The CCB effect was further confirmed when pretreatment of the tissues with piperine (10–100 μM) caused a rightward shift in the Ca++ concentration–response curves (CRCs) in Ca++-free medium, similar to that caused by verapamil. Loperamide also caused the inhibition of spontaneous and high K+-induced contractions as well as shifted the Ca++ CRCs to the right at concentrations of 1–10 μM. These data indicate that piperine exhibits antidiarrheal and antispasmodic activities, mediated possibly through calcium channel blockade.

Antidiarrhoeal activity of Geranium incanum Burm. f. (Geraniaceae) leaf aqueous extract in mice

Ethnopharmacological relevance Geranium incanum Burm. f. (Geraniaceae) is used in South Africa especially in rural communities by traditional medicine practitioners to treat diarrhoea. However, scientific evidence does not exist in any literature to corroborate the claim of therapeutic success of the plant species in diarrhoea. Aim of study The study intended to investigate the antidiarrhoeal activity of the leaf aqueous extract of Geranium incanum in mice. Materials and Methods Castor oil induced diarrhoeal test was used to assess the antidiarrhoeal activity of Geranium incanum. Gastrointestinal tract transit of charcoal meal test was used to assess the antipropulsive activity of the plant extract while the acute toxicity study and phytochemical analysis were carried out using well established protocols and methods. Results The antidiarrhoeal activity of Geranium incanum was investigated by studying the effect of leaf aqueous extract of the plant species on castor oil-induced diarrhoea in mice. The leaf aqueous extract of Geranium incanum significantly reduced faecal output in castor oil -induced diarrhoea and also significantly reduced the number of diarrhoeal episodes. Geranium incanum significantly delayed the onset of diarrhoea induced by castor oil and significantly reduced the number of animals exhibiting diarrhoea. Loperamide, a standard antidiarrhoeal drug, produced similar effects to the leaf aqueous extract of Geranium incanum on castor oil-induced diarrhoea. Both Geranium incanum and loperamide significantly reduced the intestinal propulsion of charcoal meal in mice. The phytochemical analysis of the leaves revealed the presence of tannins, saponins particularly steroidal saponin, and flavonoids. The LD 50 of the plant species obtained was greater than 4000 mg/kg (p.o.). Conclusion The data obtained indicate that the leaf aqueous extract of Geranium incanum has both antidiarrhoeal and antipropulsive activities The data also show that the plant material given orally may be safe and/or non toxic in mice. However, further investigation on the acute toxicity and on the mechanism of the antidiarrhoeal effect of the plant species needs to be carried out.

Anti-Diarrheal Activity Of The Leaf Extracts Of &lt;i&gt;Daniellia oliveri&lt;/i&gt; Hutch And Dalz (Fabaceae) And &lt;i&gt;Ficus sycomorus &lt;/i&gt; Miq (Moraceae)

The leaves of the plants Daniellia oliveri (Fabaceae) and Ficus sycomorus (Moraceae) used in diarrhea treatment in Hausa ethnomedicine of Northern Nigeria were investigated. The study was carried out on perfused isolated rabbit jejunum and castor oil-induced diarrhea in mice. The n-butanol extracts: NBD and NBF (0.16-3.2 mg/ml) caused a dose-dependent relaxation of isolated rabbit jejunum. The acute toxicity test for NBD and NBT in mice established an i.p LD(50) of > 4000 mg/kg for D. oliveri and 1131.4 mg/kg for F. sycomorus. In castor oil-induced diarrhea, 80% protection was observed for D. oliveri at doses of 200 mg/kg and 60% protection was observed at 100 mg/kg and 50 mg/kg respectively. For F. sycomorus 100% protection was observed at doses of 120 mg/kg and 60 mg/kg, for the n-butanol extract. The antidiarrheal activity was comparable to loperamide 5 mg/kg. The result revealed that the extracts have pharmacological activity against diarrhea.

Antidiarrhoeal property of the hydroethanolic extract of the flowering tops of Anthocephalus cadamba

The antidiarrhoeal property of the hydroethanolic extract of the flowering tops of Anthocephalus cadamba was assessed on experimental animals. The dry hydroethanolic extract (250-500 mg/kg body mass, p.o.) exhibited a dose-dependent decrease in the total number of faecal droppings in castor oil-induced diarrhoea in mice. The extract also produced a significant (p < 0.01) and dose-dependent reduction in intestinal fluids accumulation and in the gastrointestinal transit from 64.59 % and 71.19% at doses of 250 and 500 mg/kg. The reduction rates were 37.85% and 74.91%, respectively, with the control and standard drug group.

Antinociceptive and antidiarrhoeal activities of Bruguiera gymnorrhiza

The methanol extract of leaves of Bruguiera gymnorrhiza (L.) Lam. (Rhizophoraceae) was screened for its antinociceptive and antidiarrhoeal activities. The extract produced significant inhibition in acetic acid-induced writhing in mice at dose of 250 and 500 mg/kg body weight (P < 0.001), comparable to the standard drug diclofenac sodium at the dose of 25 mg/kg of body weight (P < 0.001). When tested for its antidiarrhoeal effects on castor oil-induced diarrhea in mice, it increased mean latent period (P < 0.02) and decreased the frequency of defecation (P < 0.01) significantly at the dose of 500 mg/kg body weight, comparable to the standard drug loperamide at the dose of 50 mg/kg of body weight. The overall results tend to suggest the antinociceptive and antidiarrhoeal activities of the extract.

Antidiarrheal activity of dehydroleucodine isolated from Artemisia douglasiana

Dehydroleucodine (DhL), a sesquiterpene lactone obtained from Artemisia douglasiana, was screened for antidiarrheal effects. DhL inhibited castor oil-induced diarrhea in mice by judged by a decrease in the number of wet faeces in the DhL-treatment groups. DhL significantly reduced intestinal transit in mice. Yohimbine and phentolamine counteracted the inhibitory effect of DhL. It is suggested that α 2-adrenergic receptors mediate the effect of DhL in intestinal motility. DhL reduced also intraluminal accumulation of fluid. Thus, the antidiarrheal activity of DhL is possibly related, at least in part, to its inhibitory action against gastrointestinal motility and the inhibition of enteropooling property.