The Effects of Different Forms of Zeatin on Prepulse Inhibition and Anxiety

In this study, behavioral responses to various doses of trans-zeatin (tZ) and trans-zeatin riboside (tZR) on prepulse inhibition following sleep deprivation and anxiety in 12-14 week old Wistar Albino rats (n=128) were examined.

In sleep deprivation experiments, prepulse inhibition test and locomotor activity test were performed to 8 groups of rats (n=64) that were deprived of sleep for 72 hours using the modified multiple platform technique, following administration of vehicle or tZR intraperitoneally at doses of 2.5-5-10-20 mg/kg or 2.5-5-10 mg/kg, respectively. The groups are as follows: 1) SD control (vehicle) group, 2) SD 2,5 mg/kg tZ group, 3) SD 5 mg/kg tZ group, 4) SD 10 mg/kg tZ group, 5) SD 20 mg/kg tZ group, 6) SD 2,5 mg/kg tZR group, 7) SD 5 mg/kg tZR group, 8) SD 10 mg/kg tZR group. All.data.part.1 excel file shows the data of all groups for basal mean PPI values, mean PPI values in 74/78/86 db prepulse stimuli respectively, startle values, weights, and locomotor activity values (at 10 min time bins and total).

In anxiety experiments, the elevated plus maze test was applied to 8 groups of rats (n=64) who were administered intraperitoneally with vehicle or tZ at doses of 2.5-5-10 mg/kg, or tZR at doses of 2.5-5-10-20 mg/kg, respectively. The groups are as follows: 1) Control (vehicle) group, 2) 2,5 mg/kg tZ group, 3) 5 mg/kg tZ group, 4) 10 mg/kg tZ group, 5) 2,5 mg/kg tZR group, 6) 5 mg/kg tZR group, 7) 10 mg/kg tZR group, 8) 20 mg/kg tZR group. All.data.part.2 excel file shows the data of all groups for entries into closed arm (EICA), entries into open arm (EIOA), time spent in closed arm (TSICA), time spent in open arm (TSIOA), entries into closed arm percentage (EICA%), entries into open arm percentage (EIOA%), time spent in closed arm percentage (TSICA%), time spent in open arm percentage (TSIOA%) , and weights.

It was found in the study that the doses of tZ 5 mg/kg and tZR 20 mg/kg had anxiogenic effects in anxiety experiments. In sleep deprivation experiments, however, tZ and tZR did not reverse impaired prepulse inhibition at any dose, and did not show a significant effect on startle levels and locomotor activity. These results indicate that tZ and tZR do not have a therapeutic effect on the psychosis model triggered by sleep deprivation in rats, and do not show anxiolytic effects, but may show anxiogenic effects on the contrary.