Prior exposure to enriched environment reduces nitric oxide synthase after transient MCAO in rats.
Increasing evidence shows that exposure to an enriched environment (EE) after cerebral ischemia/reperfusion injury is neuroprotective in animal models. However, little is known about of the neuroprotective effects of EE exposure prior to injury. The current study examined the effects of prior EE exposure on inducible and neuronal nitric oxide syntheses (iNOS and nNOS) after transient middle cerebral artery occlusion (tMCAO) in rats. A total of 72 rats were exposed to EE or standard housing condition (SC) for 1 month, followed by 90-min MCAO and reperfusion or sham surgery, leading to the following three groups: (1) EE+MCAO (n=24), (2) SC+MCAO (n=24), (3) SC+sham (n=24). Rats were sacrificed at 1, 6, or 24h after MCAO (n=6/group) for iNOS and nNOS mRNA quantification by real-time PCR and at 24h after MCAO (n=6/group) for iNOS and nNOS protein quantification by Western blot or were evaluated for neurological function outcomes, then sacrificed to assess infarct volume (n=6/group). Results showed that prior exposure to EE reduced iNOS and nNOS mRNA and protein and improved neurological status after MCAO without affecting infarct volume, suggesting that EE may provide neuroprotection via ischemic preconditioning.
Department of Rehabilitation, Huashan Hospital, Fudan University, Shanghai 200040, China; State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200032, China.
Kewei
K
Yu
Yi
Y
Wu
Yongshan
Y
Hu
Qi
Q
Zhang
Hongyu
H
Xie
Gang
G
Liu
Yao
Y
Chen
Zhenzhen
Z
Guo
Jie
J
Jia
D000704:Analysis of Variance; D000818:Animals; D004195:Disease Models, Animal; D004777:Environment; D020244:Infarction, Middle Cerebral Artery / Q000150:complications / Q000517:prevention & control*; D008297:Male; D009422:Nervous System Diseases / Q000209:etiology / Q000517:prevention & control; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D011597:Psychomotor Performance / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D012333:RNA, Messenger; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II
Enriched environment; Ischemia; iNOS; nNOS