| Abstrakt: |
Objective: The aim of this study was to investigate how the inhibitory neurons expressing the different Ca2+-binding proteins of the GABAergic system will be affected with changes in Ca2+ homeostasis in BDNF deficiency and endoplasmic reticulum stress (ERS). Methods: Wild-type (WT) and BDNF heterozygous (BDNF+/-) male mice were used in 4 groups (n=7-8); WT, BDNF(+/-), WT+Tm, BDNF(+/-)+Tm. Group 3 and 4 were treated with a single dose of tunicamycin (Tm) (0.5 mg/kg, intraperitoneal) to form ERS. On the 3rd day of Tm injection, animals were sacrificed, blood and brain tissues were taken. In serum samples BDNF, in tissue homogenates GRP78, Caspase-12, Parvalbumin, Calretinin, Calbindin, GAD65 and GAD67 levels were investigated by ELISA. One-way ANOVA and Tukey tests were used for statistical evaluation. Results: Serum BDNF levels were significantly lower in BDNF(+/-) and BDNF(+/-)+Tm groups, than in WT and WT+Tm groups. GRP78 level did not show any significant difference between the groups. Caspase-12 level was similar in WT and BDNF(+/-) groups, however Tm injection significantly increased Caspase-'2 level. Parvalbumin, calretinin and calbindin levels in basal conditions were higher in BDNF(+/-) group, but this difference was not statistically significant. On the other hand, Calbindin level decreased significantly with ERS. GAD65 and GAD67 levels were similar in WT and BDNF(+/-) groups. However, GAD65 level was significantly decreased during ERS in W T and BDNF(+/-) groups. Conclusion: It is known that parvalbumin-positive neurons express GAD67, Calbindin and Calretinin-positive neurons express GAD65. Our findings suggesting a significant decrease in Calbindin and GAD65 isoform of glutamic acid decarboxylase enzyme levels during ERS indicate that the sensitivity of varied intermediate neurons in GABAergic system to ERS may be different. However, endogenous BDNF deficiency did not affect the ERS sensitivity of these intermediate neurons. [ABSTRACT FROM AUTHOR] |
