Analgesic and anti-inflammatory effects of aqueous leafextract of Combretum micranthumg. Don (Combretaceae)

The analgesic and anti-inflammatory effects of the aqueous leaf extract of Combretum micranthum were studied in mice and rats. The extract was screened for analgesic activity; using acetic acid induced writhing in mice and formalin induced paw licking test in rats. Anti-inflammatory effect was evaluated using formalin induced hind paw oedema in rats. Results showed that, at a dose of 200 mg/kg the extract significantly (p < 0.05) reduced the number of abdominal constrictions in mice and at doses of 100 and 200 mg/kg, the extract significantly (p < 0.05) reduced the licking time in rats in the formalin induced paw licking test. The extract at doses of 50,100 and 200 mg/kg significantly (p < 0.05) reduced hind paw oedema in rats from the first hour of formalin administration. The intraperitoneal LD50 value of the extract was found to be 2,154.1mg/kgin mice and 2,852.l mg/kg in rats. The analgesic and anti-inflammatory activities of the plant extract may probably be due to the presence of phytochemical contents.Keywords: Combrentum micranthum, Analgesic, Anti-inflammatory, Mice, Rats

Effect of aqueous leaf extract of Combretum Micranthum g. don (Combretaceae) on gastro intestinal smooth muscle.

The effects of the aqueous leaf extract of Combretum micranthum were studied on gastro intestinal smooth muscle of rodents. The extract was screened using isolated rabbit jejunum, guinea pig ileum and rat uterus. The extract produced relaxation of isolated rabbit jejunum and guinea pig ileum. The relaxation of guinea pig ileum was inhibited by phentolamine. The effect of the extract on rabbit jejunum and guinea pig ileum may involve adrenergic receptors. The extract had no effect on pregnant and non-pregnant isolated rat uterus. The result of preliminary phytochemical screening of the extract showed that, the aqueous leaf extract contains alkaloids, flavonoids, glycosides, saponins, tannins and phlabotannins. The properties of the extract may be due to the presence of these active constituents of pharmacological importance that bear relevance to its therapeutic claims in traditional medicine.Keywords: Combretum micranthum, Rabbit jejunum, Rat uterus and Guinea pig ileum

Sedative properties of Mitracarpus villosus leaves in mice

The leaves of Mitracarpus villosus (Sw.) DC. (Rubiaceae) have several therapeutic applications in the West African folk medicine for the management of a plethora of stress-related diseases including headaches. This study was designed to evaluate the sedative properties of the ethylacetate extract of Mitracarpus villosus on open field (OFT), diazepam-induced sleep, staircase climbing, head-dips in the hole-board test and rota rod test in mice. Graded doses (100 – 400 mg/kg) of the extract significantly and dose-dependently prolonged the duration of diazepam-induced sleep (P<0.05), decreased the number of squares crossed in the OFT (P<0.0001), decreased number of head-dips in the hole-board test (P<0.05) and reduced steps climbing (P<0.05) in mice. The extract at the doses tested had no effect on motor coordination as observed in the rota-rod treadmill assay in mice. Our results revealed that the ethylacetate extract of Mitracarpus villosus leaves may contain psychoactive principles that are sedative in nature, thus supporting further development of the psychoactive components of this plant for management of stress-related diseases.Keywords: Mitracarpus villosus, sedation, diazepam, locomotion

A comparative evaluation of pentazocine and dipyrone on diazepam-induced sleep in mice

This work reports on the evaluation of pentazocine and dipyrone analgesics on diazepam-induced sleep in mice. Diazepam (10 mg/kg) administered intraperitoneally (ip) was used to determine the onset and duration of sleep in mice and the mean of both set values were calculated and recorded. Pentazocine 20, 30 and 50 mg/kg administered (ip) was found to significantly decrease the onset of diazepam (10 mg/kg) induced sleep dose dependently (

Some behavioural studies on methanol root bark extract of Burkea africana (fabaceae) in mice

Burkea africana is a plant that belongs to then family Fabaceae; it is widely spread in tropical Africa including Nigeria. It is of valuable in ethnomedicine especially in the treatment of antidote for venomous stings and bites, cutaneous and sub cutaneous parasitic infection, convulsion and pulmonary troubles. The research was conducted to evaluate some central nervous system properties of the root bark methanol extractof B. africana in mice. It involved the following animal models: diazepam-induced sleep, hole-board and walking beam assay. Results: The methanol extract showed a significant decrease in the onset of sleep at doses of 40 mg/kg and 80 mg/kg (p<0.05); as well as produced significant increase in the duration of sleep (40 and 80 mg/kg) at p<0.05, p<0.005 respectively. The number of head dips significantly increased at 20 and 80 mg/kg (p<0.05 and 0.005 respectively). From the beam walking test for motor deficits, the result showed a significant increase in the number of foot slips at doses of 20 mg/kg (p<0.05); 40 and 80 mg/kg (p<0.005), where as there was no significant difference in the time taken to cross the two ends of the beam (time taken to complete the task). The median lethal dose (LD50) value of B. africana extract was found to be 288.5 mg/kg (i.p) in mice. The preliminary phytochemical screening revealed the presence of carbohydrates, saponins, flavonoid, aglycones, tannins, anthraquinones, cardiac glycosides, unsaturated steroids and triterpenes. Our results suggest that the B. africana extract contains biologically active compounds with potential sedative and anxiolytic properties.Key Words: Sedation, B. Africana, Diazepam, ethnomedicin

Effect of ingestion of ethanol extract of garcinia kola seed on erythrocytes in wistar rats

The objective of this study is to investigate the effect of ingestion of crude ethanol extract of Garcinia Kola seed on erythrocytes. Fifty male Wistar rats with average weight of 200g were divided into 5 treatment groups of 10 rats per group. Group A, served as the control and was fed with standard animal feed only while groups B, C, D and E which were the treatment groups, in addition were force-fed 2g/kg/rat/day of the Ethanol extract of Garcinia Kola seed for 1,2,3 and 4 weeks respectively by means of an endogastric tube and syringe. At the end of the experimental period for each group the animals were sacrificed and the erythrocyte number, park cell volume (PCV), and heamogloin concentration values were determined. The result on analysis showed that erythrocyte-count, PCV and haemoglobin concentration values showed significantly decreased values (p0.05) when compared with Group A. None of the values fell below the normal physiological range of the experimental animals. This shows that Garcinia Kola seed which has flavonoids as its active constituent has no long term significant toxicological implication with respect to the concentration given on the erythrocytes of mammals. Keywords: garcinia kola, erythrocytes, wistar rats, flavonoid Nigerian Journal of Physiological Sciences Vol. 20(1&2) 2005: 30-3

The Effect of Histamine on the Rat Oestrous Cycle

Intracerebroventricular (icv) administration of histamine (80-120mg) to adult Wistar rats was found to induce irregular cycles and, at times, persistent oestrous cycle when administered at different stages of the cycle. Cimetidine (50 mg/kg), a H2-receptor antagonist, administered intraperitoneally (ip) produced a transient change in the cycle, which returned to normal rhythm after a day or two. Triprolidine (50 mg/kg; ip), a H1-receptor antagonist, showed no changes in the oestrous rhythm while chlorpheniramine (50 mg/kg; ip), another H1-receptor antagonist, produced a non-significant degree of changes in the cycle. Drugs were administered at proestrus (P) oestrus (E), metoestrus (M) and dioestrus (D) of the cycle. Older rats exhibited more cycling irregularities than the younger ones when they were injected with histamine. These results suggest that histamine could play a role in reproduction as higher levels of histamine may be liable to cause adverse changes or damage to the clock mechanism (suprachiasmatic nucleus) controlling the gonadotrophin secretion and thus affect the reproductive functions. Key Words: Effect of histamine, oestrous cycle, rat. Résumé L'administration intracerebroventriculaire(ICV) de l'histamine(80-120mg)chez les “wistar rats” s'est avérée induire des cycle irreguliers et par moment des cycle œstru persistant quand administré à different stades du cycle. La cimetidine(50mg/kg),un recepteur-H2 antagoniste administre par voie intrapéritoneal(ip)générait un changement transitoire dans le cycle qui retournait a son rythme normal un ou deux jours après. La Tripolidine(50mg/kg,ip) un recepteur H1 antagonist ne montrait aucun changement dans le cycle œstral alors que le chlorpheniramine(50mg/kg,ip) un autre recepteur H1 Antagonist produisait un degrée de changement non significatif dans le cycle. Les médicaments ont été administrés à des périodes proœstral œstral, metaœstral et diœstral du cycle. Les souris les plus agées exhibère plus d'irrégularité dans leur cycle que les jeunes quand elles étaient injecter a l'histamine. Ces resultants sugèrent que l'histamine peut jouer un rôle dans la reproduction puisque des dose élevées peuvent causer des changement adverses.ou des degats au mechanisme de l'horloge interne(suprachiasmatique) qui contrôle la sécretion des gonadotrophines. Et ce sur la reproduction. Mot clés: effet histaminique, cycle œstrus, souris West Afr. J. Pharmacol. Drug Res. Vol.19 (1&2) 2003: 47-5

Analgesic and anti-flammatory activities of the aqueous leaf extract of Solanum nigrum Linn (solanaceae) in rats

The analgesic and anti-inflammatory activities of aqueous leaf extract of S. nigrum was investigated in rats. Thermally-induced pain and pressure-induced pain were used to assess the analgesic activity of the extract while egg albumin-induced oedema was used for anti-inflammatory activity. The aqueous leaf extract of S. nigrum at doses of 30 mg/kg and 60 mg/kg, ip exhibited a significant (

Psychopharmacological properties of the saponin fraction of Ficus platyphylla stem bark

The psychopharmacological effects of a saponin-rich fraction (SFG) obtained from crude methanolic extract of Ficus platyphylla stem bark were studied on spontaneous motor activity (SMA), pentobarbitalinduced sleep, motor coordination, amphetamine-induced hyperactivity and stereotyped behaviour, catalepsy, forced swim and tail suspension tests in rodents. SFG reduced SMA dose dependently, suggesting that it may contain psychoactive principles with sedative effects. The fraction shortened the onset and prolonged the duration of pentobarbital-induced sleep, which confirmed its sedative properties. The fraction diminished immobility time in forced swim and tail suspension tests, which is indicative of antidepressant properties. It attenuated amphetamine-induced hyperactivity and stereotyped behaviour, induced catalepsy and exacerbated haloperidol-induced catalepsy in rodents, but had no effect on motor coordination in the treadmill experiment at the doses tested. These effects were similar to those of classical neuroleptics and antidepressants. Our study provides scientific evidence of psychopharmacological effects of the saponin fraction of Ficus platyphylla stem bark and therefore supports further development of its psychoactive components as antipsychotics and antidepressants. Keywords: Ficus platyphylla, depression, psychosis, sedation, spontaneous motor activity, stereotyped behaviour. Int. J. Biol. Chem. Sci. Vol. 2 (3) 2008: pp. 239-24

Behavioural Effects of the Methanolic Root Bark Extract of Securinega Virosa in Rodents

Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25–25mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant