Inhibition of neuronal nitric oxide synthase increases adrenalectomy-induced granule cell death in the rat dentate gyrus.
Recent studies have shown that the expression of neuronal nitric oxide synthase (NOS) mRNA is increased after adrenalectomy (ADX). However, the role of increased NO production after ADX in the dentate gyrus is unknown. In this study, the relationship between NO inhibition and apoptosis in the dentate gyrus after ADX was examined. 7-Nitroindazole (7-NI; 30 mg/kg, i.p.), a selective inhibitor of neuronal NOS, was injected 1 day before ADX and subsequently once every 24 h. Then 4 days after ADX, dentate granule cell death was evaluated using silver impregnation and Nissl staining methods. Inhibition of neuronal NOS by 7-NI increased the number of dying granule cells approximately 4-fold in the dentate gyrus of the ADX rats, compared to vehicle-injected ADX controls. These results suggest that increased NO production after ADX may play an endogenous neuroprotective role in the dentate gyrus.
Park
Chan
C
Department of Anatomy, College of Medicine, Kohwang Medical Research Institute, Kyunghee University, Hoeki-Dong 1, Dongdaemun-Gu, Seoul, 130-701, South Korea.
Kang
Minjeong
M
Kim-Kwon
Yunhee
Y
Kim
Junghye
J
Ahn
Heekyung
H
Huh
Youngbuhm
Y
D000315:Adrenalectomy; D000818:Animals; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D018891:Dentate Gyrus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007191:Indazoles / Q000494:pharmacology*; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D052248:Nitric Oxide Synthase Type I; D051381:Rats; D011916:Rats, Inbred F344
D004791:Enzyme Inhibitors; D007191:Indazoles; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat; C080122:7-nitroindazole