**3. Results**

26 Neuroendocrinology and Behavior

**Figure 8.** Rat is on the platform after it found the hidden platform.

**Figure 9.** Total distance travelled is high. Time to find the platform is long.

Data were analyzed using SPSS (SPSS Statistical Software, SPSS Inc., Los Angeles, CA, USA, Ver. 15.0). A 2 (pinealectomy and control) X 4 (treatments: saline, diazepam, 1 μg/kg melatonin and 100 μg/kg melatonin) ANOVA analyses on data were performed with the last factor as a within subject or repeated design. Significant ANOVA results were also tested by the post test, namely the Tukey test which is assumed to be a strong test for comparison of groups that has equal variance and sample size. Values were considered statistically significant at p ≤ 0.05. Data are presented as MEAN SEM after back

**2.10. Statistical analyses** 

transforming from ANOVA results.

#### **3.1. Anxiety measures**

#### *3.1.1. Open field measurements*

#### *3.1.1.1. Total distance travelled*

An interaction effect between the group and the treatment was significant on the total distance travelled on the open field, *F*(3, 36) = 6.15, *p* < 0.002, η2 = .34. This effect reflected the fact that in control condition subjects received 100 μg/kg melatonin (M = 699.65) and 1 μg/kg melatonin (M = 690.46) treatments travelled less distance than those received diazepam (M = 1400.04) and saline (M = 1214.95), whereas in the pinealectomy condition, the subjects received diazem (M = 643.75) travelled less distance than those received 100 μg/kg melatonin (M = 1070.22), 1 μg/kg melatonin (M = 914.38) and saline (M = 902.11) treatments.

**Figure 10.** The total distance travelled. Right striated bar represents the saline injection and black bar represents diazepam injections, cross striated bar represents 1 μg/kg melatonin injection and bricks striated bar represents 100 μg/kg melatonin injection for both control and pinealectomy groups. Data are presented as means (± S.E.M.). Different letters indicate the statistically different groups. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

#### *3.1.1.2. Time spent at the edge of the open field (Edge duration)*

An interaction effect between the group and the treatment was also significant, *F* (3, 36) = 5.38, *p* = .004, η2 = .31. Indicating that in control condition subjects received diazepam spent less time than the other treatments whereas, in pinealectomy condition the subjects were not significantly different from each other.

#### *3.1.1.3. Time spent at the center of the open field (Center duration)*

The interaction effect between the group and the treatment was also significant, *F*(3, 36) = 5.29, *p* < 0.004, η2 = .31. Indicating that in control condition subjects received diazepam spent

more time than the other treatments whereas, in pinealectomy condition the subjects were not significantly different from each other.

Intraamygdalar Melatonin Administration and Pinealectomy Affect Anxiety Like Behavior and Spatial Memory 29

saline was more mobile than the other treatments, whereas in pinealectomy condition the subjects who received 100 μg/kg melatonin treatment were more mobile than the other

**Figure 12.** The entrance frequency to the center of the open field. The bar explanations can be seen in

Figure 10. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

**Figure 13.** The mobility time . The bar explanations can be seen in Figure 10. (Reproduced with

received 100 μg/kg melatonin treatment were faster than the other treatments.

The interaction effect between the group and the treatment was significant, *F* (3, 36) = 6.52, *p* < 0.001, η2 = .35, indicating that in control condition subjects received saline and diazepam were faster than the other treatments, whereas in pinealectomy condition the subjects who

permission from Karakas et al.; published by Elsevier, 2011a.)

*3.1.1.7. Velocity* 

treatments.

**Figure 11.** The time spent at the center of the open field. The bar explanations can be seen in Figure 10. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

#### *3.1.1.4. Entrance frequency to the edge of the open field (Edge frequency)*

The interaction effect between the group and the treatment was significant, *F*(3, 36) = 3.02, *p* < 0.04, η2 = .20, reflecting the fact that in control condition subjects received diazepam entered more frequently to the edge of the open field than the other treatments, whereas in pinealectomy condition the subjects who received saline treatment entered more frequently than the other treatments.

#### *3.1.1.5. Entrance frequency to the center of the open field (Center frequency)*

The interaction effect between the group and the treatment was significant, *F*(3, 36) = 3.02, *p* < 0.04, η2 = .20, reflecting the fact that in control condition subjects received diazepam entered more frequently to the center of the open field than the other treatments, whereas in pinealectomy condition the subjects who received saline treatment entered more frequently than the other treatments.

#### *3.1.1.6. Mobility*

The main effect of the group was significant, *F* (1, 36) = 6.89, *p* = .01, η2 = .16. Control group was more mobile than pinealectomy group. The main effect of the treatment was also significant, *F* (3, 36) = 6.73, *p* = .001, η2 = .36. The subjects who received saline were more mobile on the open field than the other subjects with each being not significantly different from each other.

In addition, the interaction effect between the group and the treatment was significant, *F*(3, 36) = 7.08, *p* < 0.001, η2 = .37. This reflected the fact that in control condition subjects received

saline was more mobile than the other treatments, whereas in pinealectomy condition the subjects who received 100 μg/kg melatonin treatment were more mobile than the other treatments.

**Figure 12.** The entrance frequency to the center of the open field. The bar explanations can be seen in Figure 10. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

**Figure 13.** The mobility time . The bar explanations can be seen in Figure 10. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

#### *3.1.1.7. Velocity*

28 Neuroendocrinology and Behavior

than the other treatments.

than the other treatments.

*3.1.1.6. Mobility* 

from each other.

not significantly different from each other.

more time than the other treatments whereas, in pinealectomy condition the subjects were

**Figure 11.** The time spent at the center of the open field. The bar explanations can be seen in Figure 10.

The interaction effect between the group and the treatment was significant, *F*(3, 36) = 3.02, *p* < 0.04, η2 = .20, reflecting the fact that in control condition subjects received diazepam entered more frequently to the edge of the open field than the other treatments, whereas in pinealectomy condition the subjects who received saline treatment entered more frequently

The interaction effect between the group and the treatment was significant, *F*(3, 36) = 3.02, *p* < 0.04, η2 = .20, reflecting the fact that in control condition subjects received diazepam entered more frequently to the center of the open field than the other treatments, whereas in pinealectomy condition the subjects who received saline treatment entered more frequently

The main effect of the group was significant, *F* (1, 36) = 6.89, *p* = .01, η2 = .16. Control group was more mobile than pinealectomy group. The main effect of the treatment was also significant, *F* (3, 36) = 6.73, *p* = .001, η2 = .36. The subjects who received saline were more mobile on the open field than the other subjects with each being not significantly different

In addition, the interaction effect between the group and the treatment was significant, *F*(3, 36) = 7.08, *p* < 0.001, η2 = .37. This reflected the fact that in control condition subjects received

(Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

*3.1.1.4. Entrance frequency to the edge of the open field (Edge frequency)* 

*3.1.1.5. Entrance frequency to the center of the open field (Center frequency)* 

The interaction effect between the group and the treatment was significant, *F* (3, 36) = 6.52, *p* < 0.001, η2 = .35, indicating that in control condition subjects received saline and diazepam were faster than the other treatments, whereas in pinealectomy condition the subjects who received 100 μg/kg melatonin treatment were faster than the other treatments.

**Figure 14.** The velocity. The bar explanations can be seen in Figure 10. (Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

Intraamygdalar Melatonin Administration and Pinealectomy Affect Anxiety Like Behavior and Spatial Memory 31

**Figure 15.** The total distance travelled. Right striated bar represents the saline injection and black bar represents diazepam injections, cross striated bar represents 1 μg/kg melatonin injection and bricks striated bar represents 100 μg/kg melatonin injection for both control and pinealectomy groups. Data

are presented as means (± S.E.M.). Different letters indicate the statistically different groups.

**Figure 16.** The time spent in open arms (TSOA). The bar explanations can be seen in Figure 15.

The main effect of the treatment was significant, *F* (3, 39) = 6.56, *p* = .001, η2 = .34. The subjects who received 100 μg/kg melatonin treatment spent less time in closed arms than

(Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)

*3.1.2.3. Time spent in closed arms (Closed arm duration)* 

those who received other treatments.

(Reproduced with permission from Karakas et al.; published by Elsevier, 2011a.)
