L Xiong1, Z Zhu, H Dong, W Hu, L Hou, S Chen. 1. Department of Anesthesiology, Xijing Hospital of the Fourth Military Medical University, Xi'an 710032, China.
Abstract
OBJECTIVE: This study was designed to determine if repeated hyperbaric oxygen (HBO) exposure induces ischemic tolerance in focal cerebral ischemia. METHODS: Sixty male SD rats were used in this study. Thirty animals underwent transient middle cerebral artery occlusion (MCAO) and the other thirty permanent MCAO model. The rats were randomly allocated to 3 sub-groups: control group (n = 10), HBO-3 group (n = 10), and HBO-5 group (n = 10). The animals in HBO-3 and HBO-5 groups received 1 hour hyperbaric oxygenation at 2.5 atmosphere absolute (ATA) in 100% oxygen every day for 3 and 5 days, respectively. The animals in the control group received sham treatments. 24 hours after the last HBO, transient MCAO (120 min) and permanent MCAO were induced by introducing a 3-0 nylon monofilament suture through internal carotid artery based on the Koizumi technique. The neurological outcome was evaluated until 24 hours after reperfusion in transient MCAO rats and ischemia in permanent MCAO rats. The infarct volume was then assessed by TTC staining. RESULTS: In transient MCAO rats, the neurological outcome in both the HBO-3 and HBO-5 groups was better than that of the control group (P < 0.05 and 0.001). The infarct volume decreased from 171.5 +/- 113 mm3 to 40.6 +/- 49.9 mm3(P < 0.05) in the HBO-3 group and 16.2 +/- 28.8 mm3(P < 0.01) in the HBO-5 group. There were no significant differences in neurological outcome and infarct volume among the three groups in permanent MCAO rats. CONCLUSIONS: The present study demonstrated that HBO preconditioning can induce ischemic tolerance in transient not permanent MCAO rats in a "dose-dependent" manner.
OBJECTIVE: This study was designed to determine if repeated hyperbaric oxygen (HBO) exposure induces ischemic tolerance in focal cerebral ischemia. METHODS: Sixty male SD rats were used in this study. Thirty animals underwent transient middle cerebral artery occlusion (MCAO) and the other thirty permanent MCAO model. The rats were randomly allocated to 3 sub-groups: control group (n = 10), HBO-3 group (n = 10), and HBO-5 group (n = 10). The animals in HBO-3 and HBO-5 groups received 1 hour hyperbaric oxygenation at 2.5 atmosphere absolute (ATA) in 100% oxygen every day for 3 and 5 days, respectively. The animals in the control group received sham treatments. 24 hours after the last HBO, transient MCAO (120 min) and permanent MCAO were induced by introducing a 3-0 nylon monofilament suture through internal carotid artery based on the Koizumi technique. The neurological outcome was evaluated until 24 hours after reperfusion in transient MCAOrats and ischemia in permanent MCAOrats. The infarct volume was then assessed by TTC staining. RESULTS: In transient MCAOrats, the neurological outcome in both the HBO-3 and HBO-5 groups was better than that of the control group (P < 0.05 and 0.001). The infarct volume decreased from 171.5 +/- 113 mm3 to 40.6 +/- 49.9 mm3(P < 0.05) in the HBO-3 group and 16.2 +/- 28.8 mm3(P < 0.01) in the HBO-5 group. There were no significant differences in neurological outcome and infarct volume among the three groups in permanent MCAOrats. CONCLUSIONS: The present study demonstrated that HBO preconditioning can induce ischemic tolerance in transient not permanent MCAOrats in a "dose-dependent" manner.
Authors: Robert P Ostrowski; Gerhart Graupner; Elena Titova; Jennifer Zhang; Jeffrey Chiu; Neal Dach; Dalia Corleone; Jiping Tang; John H Zhang Journal: Neurobiol Dis Date: 2007-07-28 Impact factor: 5.996
Authors: Cesar Reis; Yuechun Wang; Onat Akyol; Wing Mann Ho; Richard Applegate Ii; Gary Stier; Robert Martin; John H Zhang Journal: Int J Mol Sci Date: 2015-05-26 Impact factor: 5.923