Effect of functional pinealectomy on hippocampal lipid peroxidation, antioxidant enzymes and N-methyl-D-aspartate receptor subunits 2A and 2B in young and old rats.
OBJECTIVE
To investigate the effects of pinealectomy on lipid peroxidation, antioxidant status and NMDA receptor subunits 2A and 2B concentrations in hippocampus.


METHODS
Forty-eight male Wistar-albino rats were used.


METHODS
Animals were divided into three groups: 24 h dark throughout the study (highest melatonin release), 24 h light exposure (light-induced functional pinealectomy) and 12 h light/12 h dark exposure (control group). Thereafter, each group was divided into two groups as young and old animals.


RESULTS
There was an increase in NR2A and NR2B concentration in DY group compared to all other treatments. CuZn and Mn SOD activities were found to be increased in CO compared to CY group. Continual light exposure for 4 weeks did not change neural CuZn and Mn SOD activities. In old rats, light exposure reduced the activities of both CuZn and Mn SOD relative to those in the young animals. In addition, CuZn and Mn SOD activities were higher in dark exposed rats than in those in the continual light exposed or LD 12:12 rats. GSH-Px activity was found elevated in the DY rats compared to the CY groups. MDA levels were significantly higher in the CO than in the CY group.


CONCLUSIONS
NR2A and NR2B receptor concentrations in hippocampus of the rats maintained in dark showed significant increases compared to the control and functional pinealectomy groups but there was no significant increase in lipid peroxidation.
Delibas
Namik
N
School of Medicine, Department of Biochemistry and Clinical Biochemistry, Suleyman Demirel University, 32260 Isparta, Turkey. ndelibas@hotmail.com
Tuzmen
Nalan
N
Yonden
Zafer
Z
Altuntas
Irfan
I
D000375:Aging / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D003624:Darkness; D006624:Hippocampus / Q000201:enzymology*; D008029:Lighting; D015227:Lipid Peroxidation / Q000502:physiology; D008297:Male; D010870:Pineal Gland / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism*
D000975:Antioxidants; D016194:Receptors, N-Methyl-D-Aspartate; D013482:Superoxide Dismutase; C121001:NR2B NMDA receptor