3

INTRODUCTION

Aluminium, a dementing ion, has been excluded through out

the course of

evolution

despite

its

environmental

abundance.

aluminium

With

continued

acidification

of

our

environment

bioavailability will continue to increase [10]. Aluminium has

been

implicated

in

the

pathology

of

several

neurological

disorders associated with cognitive impairments [19]. Aluminium

has been suggested as a cholinotoxin [7] and animals exposed to

aluminium

as

animal

models

for

Alzheimer's

disease

[20].

In

Alzheimer's disease neurofibrillary degeneration is associated

with pronounced deficits in choline acetyltransferase [16] and

acetylcholinesterase [2].

distinct

experimental

cholinergic

animals

deficit.

aluminium

exposure

results

in

and

Though

ultrastructural

immunological

neurofibrillary

studies

have

shown

that

aluminium

induced

degeneration

differs

from

Alzheimer's

neurofibrillary tangles, other findings ranging

from

elevated

aluminium

levels

in

brain

tissue

of

demented

patients

to

extensive research at cellular and subcellular levels have kept

the issue of aluminium neurotoxicity open.