strychnine and thiosemicarbazide

The decoction from the stem bark of Psychotria camptopus (Rubiaceae) is used in the Cameroonian pharmacopoeia to treat neurological pathologies including epilepsy.. The present work was undertaken to study the anticonvulsant properties of the aqueous (AE) and methanol (ME) extracts from the stem bark of P. camptopus in acute models of epileptic seizures in Wistar rats.. AE and ME were obtained by decoction and maceration of the stem bark powder in water and methanol, respectively. They were tested orally at the doses of 40, 80 and 120 mg/kg, on the latency of onset and duration of epileptic seizures induced by pentylene tetrazole (PTZ, 70 mg/kg, i.p.). The kinetic effect of both extracts at 120 mg/kg was evaluated. Their effects on diazepam (50 mg/kg) induced sleep and strychnine (STR, 2.5 mg/kg, i.p.) induced seizures were determined. ME was further tested on picrotoxin (PIC, 7.5 mg/kg, i.p.) and thiosemicarbazide (TSC, 50 mg/kg, i.p.) induced seizure models. The phytochemical composition of ME was assessed using LC-MS method, as well as its acute toxicity.. AE and ME significantly (p < 0.001) reduced the duration of seizures in both PTZ and STR models. Their maximal effect was observed at 1 h after administration, though their effect at 120 mg/kg was maintained (p < 0.05) up to 24 h post-treatment. Both extracts significantly (p < 0.01) reduced sleep duration. ME significantly (p < 0.001) increased the latency of rat death on PIC-induced convulsions. In TSC rats, ME significantly (p < 0.001) delayed the latency to the first convulsion, and decreased the duration and frequency of convulsions. ME showed no acute toxicity while its phytochemical screening revealed the presence of two flavonoids (Rutin and Butin), two triterpenoid saponins (Psycotrianoside B and Bauerenone) and four alkaloids (10-Hydroxy-antirhine, 10-hydroxy-iso-deppeaninol, Emetine and Hodkinsine). In conclusion, AE and ME from the stem bark of P. camptopus have comparable anticonvulsant properties. The effect of ME is likely due to the presence of flavonoids and alkaloid and the activation of GABA pathway. These results further justify and support the use of P. camptopus in traditional medicine for the treatment of epilepsy.

Topics: Animals; Anticonvulsants; Behavior, Animal; Diazepam; Disease Models, Animal; Epilepsy; Methanol; Mice; Pentylenetetrazole; Phytochemicals; Picrotoxin; Plant Bark; Plant Extracts; Plant Stems; Psychotria; Rats, Wistar; Seizures; Semicarbazides; Sleep; Sleep Latency; Strychnine; Water

The anticonvulsant activity of bis(acetato)tetrakis(imidazole) copper(II), Cu(OAc)2(Im)4, was studied in normal mice using chemical convulsions induced by strychnine, thiosemicarbazide, picrotoxin, and pentelenetetrazol. Intraperitoneal administration of Cu(OAc)2(Im)4, 50 mg/kg body mass, has delayed the onset of strychnine (3 mg/kg)-induced convulsion by 204% (p < or = 0.005) and thiosemicarbazide (20 mg/kg)-induced convulsant by 61% (p < or = 0.005). The changes in the onset of picrotoxin- (6 mg/kg) and pentelenetetrazol (50 mg/kg)-induced convulsions were not significant. The same dosage of the copper compound was effective in delaying the lethal time and reducing the mortality rate of treated animals. The anticonvulsant activity of Cu(OAc)2(Im)4 complex against strychnine was not related to its constituents because the inorganic form of copper such as copper chloride, copper acetate, and the parent imidazole has no anticonvulsant activity. Other copper(II) complexes like copper(II)aspirinate and bis(acetato)bis(2-methyl imidazole) copper(II) were less effective.

Topics: Animals; Anticonvulsants; Female; Mice; Organometallic Compounds; Seizures; Semicarbazides; Strychnine; Time Factors

Orally administered amitryptiline (25 and 50 mg/kg) protected animals against fatal convulsions induced by thiosemicarbazide, strychnine and metrazole. Vilaxazine had a protecting effect against death induced by strychnine. Impramine, maprotiline, mianserine and pirlindole (pyrazidol) only somewhat prolonged the latend period of convulsions and death, while incazane, caroxazone, nomifenzine and trazodone had practically no effect on the action of the three convulsants under study.

Topics: Animals; Anticonvulsants; Antidepressive Agents; Female; Male; Mice; Pentylenetetrazole; Semicarbazides; Strychnine