ABSTRACT

Phoenix dactylifera contains some phytochemical constituents which have been reported

to be associated with different pharmacological activities. Triterpenes and steroids,

flavonoids, cardiac glycoside among other phytochemicals have been reported to possess

anticonvulsant activity. This study therefore is aimed at evaluating the anticonvulsant

activity of aqueous extract of Phoenix dactylifera fruits using Pentylenetetrazole (PTZ),

Maximum electroshock test (MEST), Strychnine, Picrotoxin, 4-Aminopyridine (4-AP) and

Isoniazid (INH)-induced seizure. The acute toxicity study carried out on the aqueous

extract revealed that the LD50 is above 5000 mg/kg i.e the extract is practically non-toxic.

In each model of seizure, the animals were divided into 5 groups. Group 1 was

administered Normal Saline (10 ml/kg, p.o), groups 2, 3 and 4 were administered graded

doses of the aqueous extract 250 mg/kg, 500 mg/kg and 1000 mg/kg (p.o) one hour before

seizure induction while group 5 was treated with the respective standard antiepileptic drug

(i.p) thirty minute before induction of seizure. In MEST model, the extract exhibited a

significant (p<0.05) decrease in recovery time from seizure at all the tested doses. In the

Strychnine (2 mg/kg, i.m) seizure test, the extract significantly (p<0.05) delayed the onset

of hind limb tonic extensor jerks which was dose-dependent. Aqueous extract of Phoenix

dactylifera at the tested doses did not exhibit any form of delay or protection against

seizure and mortality in Pentylenetetrazole (90mg/kg, s.c), 4-AP (13.3 mg/kg, s.c),

picrotoxin (3.5 mg/kg, i.p) and INH (300 mg/kg, s.c)-induced seizures. It can therefore be

concluded that the aqueous extract of Phoenix dactylifera posseses constituents which may

be beneficial in the management of generalized tonic- clonic seizure and is possibly

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mediated via the augmentation of inhibitory neurotransmitters, possibly glycinergic

system.

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CHAPTER ONE

1.0 Introduction

The role of medicinal plants in the solution of health problems is invaluable on a global

level. Medicinal plants continue to provide valuable therapeutic agents, both in modern

and in traditional medicine (Krentz and Bailey, 2005). With the associated side effects

of the modern medicine, traditional medicines are gaining importance and are now

being studied to find the scientific basis of their therapeutic actions.

Traditional medicines, especially with medicinal plants (herbal) have been practiced

for long time in most parts of the world. In Saudi Arabia, there are many medicinal

plants with claim of neurological potential. But these claims of treatment successes are

often made without any scientific basis (Khoshnood-Mansoorkhani,and Moein, 2010).

Date palm which is commonly grown in Saudi Arabia and many parts of the World

including Nigeria is believed to have beneficial effects in the management or treatment

of neurological disorders.

Although its place of origin is unknown because of long cultivation, date probably

originated from lands around the Persian Gulf ((Walid and Marshall, 2003). The

species is widely cultivated and is reportedly naturalized in Australia, Spain, North

Africa, the Canary Islands, Madeira, Cape Verde, the Sahel region of Africa