Neurophysiological effects of an extract of Eschscholzia californica Cham. (Papaveraceae)

An aqueous alcohol extract of Eschscholzia californica (Ec) has been evaluated for benzodiazepine, neuroleptic, antidepressant, antihistaminic and analgesic properties, in order to complete the study of the sedative and anxiolytic effects previously demonstrated. The plant extract did not protect mice against the convulsant effects of pentylenetetrazol, and did not cause muscle relaxant effects but appeared to possess an affinity for the benzodiazepine receptor: thus, flumazenil, an antagonist of these receptors, suppressed the sedative and anxiolytic effects of the extract. The Ec extract induced peripheral analgesic effects in mice but did not possess antidepressant, neuroleptic or antihistaminic effects.

Effect of extracts of Orthosiphon stamineus Benth, Hieracium pilosella L., Sambucus nigra L. and Arctostaphylos uva-ursi (L.) Spreng. in rats

Aqueous extracts of Sambucus nigra and Arctostaphylos uva-ursi and hydroalcohol extracts of Orthosiphon stamineus and Hieracium pilosella were tested for their diuretic activities in rats; pharmacological evaluation revealed that they led to an increase in urine flow. Urinary sodium excretion in rats was increased with O. stamineus and S. nigra.

An analytical study, anti-inflammatory and analgesic effects of Harpagophytum procumbens and Harpagophytum zeyheri

The iridoids of Harpagophytum procumbens and Harpagophytum zeyheri were studied by CLHP. Harpagoside is the main iridoid for both drugs whereas 8-p-coumaroylharpagide is a representative iridoid of Harpagophytum zeyheri only. The ratio harpagoside/8-p-coumaroylharpagide can be used to distinguish chemically both species. For commercial dried aqueous extracts this ratio is intermediate because they are probably prepared from a mixture of H. procumbens and H. zeyheri drugs. The aqueous extracts of both drugs show similar analgesic and anti-inflammatory properties. Harpagophytum procumbens and Harpagophytum zeyheri should be accepted as sources for the drug Harpagophyti radix.

Repertory of standard herbal drugs in the Moroccan pharmacopoea

The traditional uses of plants for medicine were studied in Morocco. To this date, 231 medicinal plants belonging commonly to the Moroccan pharmacopoea have been identified and are presented in a table with the vernacular name in Arabic and/or Berber, the ecological distribution, the useful part and the medicinal use. The study of the main therapeutic indications of the medicinal plants gives a clear picture of the health problems which are treated by traditional medicine in Morocco.

Analgesic, antipyretic and anti-inflammatory properties of Euphorbia hirta

Lyophilised aqueous extract of Euphorbia hirta L. (Euphorbiaceae) has been evaluated for analgesic, antipyretic and anti-inflammatory properties in mice and rats, in order to complete its activity profile, after the confirmation of the existence of a central depressant activity particularly expressed by a strong sedative effect, associated with anxiolytic effects. This study leads us to the conclusion that this plant extract exerts central analgesic properties. Such a dose-dependent action was obtained against chemical (writhing test) and thermic (hot plate test) stimuli, respectively, from the doses of 20 and 25 mg/kg and it was inhibited by a naloxone pretreatment, a specific morphinic antagonist compound. An antipyretic activity was obtained at the sedative doses of 100 and 400 mg/kg, on the yeast-induced hyperthermia. Finally, significant and dose-dependent anti-inflammatory effects were observed on an acute inflammatory process (carrageenan-induced edema test in rats) from the dose of 100 mg/kg. On the other hand, plant extract remained inactive on chronic processes such as Freund's adjuvant-induced rheumatoid arthritis, after a chronic treatment during fourteen days at the daily dose of 200 or 400 mg/kg; however, if inefficacy was observed on rat backpaws edema and on loss of weight, the aqueous extract reduced the inflammatory hyperalgia.

Analgesic and behavioural effects of Morinda citrifolia

The traditional therapeutic indications for the use of Morinda citrifolia L. (Rubiaceae) have been investigated. The lyophilised aqueous extract of roots of M. citrifolia was evaluated for analgesic and behavioural effects in mice. The extract did not exhibit any toxic effects but did show a significant, dose-related, central analgesic activity in the writhing and hotplate tests; this effect was confirmed by the antagonistic action of naloxone. Furthermore, administration of M. citrifolia extract at high dosages decreased all behavioural parameters in the two compartment test, the light/dark choice situation test, and the staircase test; together with the induced sleeping time, these results are suggestive of sedative properties.

Influence of Anisotes trisulcus and Crepis rueppellii extracts on sites of bile formation in the rat

Anisotes trisulcus and Crepis rueppellii, two medicinal plants from Yemen, have been investigated for their hepatobiliary properties. A study of their choleretic effect and of sites of bile formation was carried out in the rat, by evaluation of bile flow, bile acids output and 14C-erythritol clearance. The data suggest that both extracts of these plants induce hypercholeresis, but Anisotes would stimulate the bile acid-dependent fraction and Crepis the bile acid-independent fraction.

Hepatoprotective properties of Crepis rueppellii and Anisotes trisulcus: two traditional medicinal plants of Yemen

Pharmacological investigations were carried out to evaluate the hepatoprotective effects of Crepis rueppellii and Anisotes trisulcus. Ethanolic extracts of these plants were investigated for their ability to reduce mortality of mice after ethanol intoxication and to lower the activities of plasma glutamic-pyruvic transaminase (GPT) after carbon tetrachloride-induced hepatitis in rats. Crepis and Anisotes extracts and a 50:50 mixture of both at 200 mg/kg presented significant hepatoprotective effects in both experimental situations. The traditional therapeutic indications of these plants have been largely confirmed.

Cultural background of the medicinal plants of Yemen

The study of the traditional use of medicinal plants of Yemen in the old pre-islamic and islamic pharmacopoeia has shown that: (1) the traditional medicine actually used in this country belongs to the old arabic medicine, itself similar to Greek and Indian medicines; (2) this medicine is highly original according to the great number of plants, indigenous or specific, of the Yemenite pharmacopoeia, which are not recorded in the literature, and to the high percentage of therapeutic indications belonging to Yemen which are unknown elsewhere.

Repertory of drugs and medicinal plants of Yemen

The traditional uses of plants for medicine were studied in the Yemen Arab Republic. To date, 130 medicinal plants have been identified and are presented in a table with the vernacular name, the geographical and ecological distribution, the medicinal use in Yemen and the pharmacological properties. Such a study of traditional medicine demonstrates the close relation between the medicinal plants and pathology.