OBJECTIVE: To evaluate the antidiarrheal effect of ethanol extract of Glycyrrhiza uralensis Fisch root (GFR) in vivo and jejunal contraction in vitro. METHODS: In vivo, 50 mice were divided into negative control, positive control (verapamil), low-, medium- and high-dose GFR (250, 500, 1,000 mg/kg) groups by a random number table, 10 mice in each group. The antidiarrheal activity was evaluated in castor oil-induced diarrhea mice model by evacuation index (EI). In vitro, the effects of GFR (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/L) on the spontaneous contraction of isolated smooth muscle of rabbit jejunum and contraction of pretreated by Acetylcholine (ACh, 10 µmol/L) and KCl (60 mmol/L) were observed for 200 s. In addition, CaCl₂ was accumulated to further study its mechanism after pretreating jejunal smooth muscle with GFR (1 and 3 g/L) or verapamil (0.03 and 0.1 µmol/L) in a Ca²⁺-free-high-K⁺ solution containing ethylene diamine tetraacetic acid (EDTA). RESULTS: GFR (500 and 1,000 mg/kg) significantly reduced EI in castor oil-induced diarrhea model mice (P<0.01). Meanwhile, GFR (0.01, 0.03, 0.1, 0.3, 1, 3, and 10 g/L) inhibited the spontaneous contraction of rabbit jejunum (P<0.05 or P<0.01). Contraction of jejunums samples pretreated by ACh and KCl with 50% effective concentration (EC₅₀) values was 1.05 (0.71-1.24), 0.34 (0.29-0.41) and 0.15 (0.11-0.20) g/L, respectively. In addition, GFR moved the concentration-effect curve of CaCl₂ down to the right, showing a similar effect to verapamil. CONCLUSIONS GFR can effectively against diarrhea and inhibit intestinal contraction, and these antidiarrheal effects may be based on blocking L-type Ca²⁺ channels and muscarinic receptors.
Mice ; Rabbits ; Animals ; Antidiarrheals/adverse effects* ; Jejunum ; Glycyrrhiza uralensis ; Castor Oil/adverse effects* ; Calcium Chloride/adverse effects* ; Diarrhea/drug therapy* ; Plant Extracts/adverse effects* ; Verapamil/adverse effects* ; Muscle Contraction

OBJECTIVETo investigate analgesic, antidiarrhoeal and cytotoxic activities of the ethanol extract of Passiflora foetida L. (Passifloraceae) by three experimental methods.

METHODSAnalgesic 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.

RESULTSThe 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.

CONCLUSIONThe 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.

Analgesics ; isolation & purification ; pharmacology ; Animals ; Antidiarrheals ; pharmacology ; Diarrhea ; chemically induced ; drug therapy ; Dose-Response Relationship, Drug ; Female ; Male ; Mice ; Pain ; drug therapy ; Passiflora ; chemistry ; Phytotherapy ; adverse effects ; methods ; Plant Extracts ; isolation & purification ; pharmacology ; toxicity