Tannins are water-soluble phenolic compounds found in plants which have the ability to form complexes with nutritionally important nutrients such as proteins and minerals. In view of the recent findings of the health benefits and classification of tannin, this study focused on assessing how plant tannin can affect or change behavioural patterns using animals exposed to pentylenetetrazol (PTZ) –induced convulsion and also compare the inhibitory role of tannin in astrocytosis. Forty nine adult male wistar rats in seven groups were used for this study. Group 1,the normal control group was given growers feed and appropriate volume of Normal saline, group 2 was given 5mg/kg of PTZ only, Groups 3, 4,5 & 6 were given tannin (100mg/kg,200mg.kg, 400mg.kg & 400mg/kg respectively) and 5mg/kg (single dose) of PTZ while group 7 (positive control group) was given 2.4mg/kg of tegretol (a control drug for convulsion) and 8.2mg/kg of PTZ. Tannin was administered orally to animals in groups 3, 4, 5 (Pre-treatment groups) and 6 for 20 days. On the 18th day of administration, PTZ administration commenced to the 20th day. Findings from this study showed that 100mg/kg and 400mg/kg of tannin had anti- convulsive properties in response to PTZ –induced convulsion, and also reduced the rate of astrocytosis in the temporal lobe. Tannin also elicited anxiolytic traits as animals pre-treated with tannin spent some time in the open arm of the EPM. Thus, tannin inhibited astrocytosis, protected neurons, reduced convulsion duration and has the potential of reducing rate of anxiety in rodents.

Keywords : Pentylenetetrazol, anxiety, astrocyte, tannin, convulsion.