JOURNAL ARTICLE

Neuronal K(ATP) channels mediate hypoxic preconditioning and reduce subsequent neonatal hypoxic-ischemic brain injury

Hong-Shuo Sun, Baofeng Xu, Wenliang Chen, Aijiao Xiao, Ekaterina Turlova, Ammar Alibraham, Andrew Barszczyk, Christine Y J Bae, Yi Quan, Baosong Liu, Lin Pei, Christopher L F Sun, Marielle Deurloo, Zhong-Ping Feng
Experimental Neurology 2015, 263: 161-71
25448006
Neonatal hypoxic-ischemic brain injury and its related illness hypoxic-ischemic encephalopathy (HIE) are major causes of nervous system damage and neurological morbidity in children. Hypoxic preconditioning (HPC) is known to be neuroprotective in cerebral ischemic brain injury. K(ATP) channels are involved in ischemic preconditioning in the heart; however the involvement of neuronal K(ATP) channels in HPC in the brain has not been fully investigated. In this study, we investigated the role of HPC in hypoxia-ischemia (HI)-induced brain injury in postnatal seven-day-old (P7) CD1 mouse pups. Specifically, TTC (2,3,5-triphenyltetrazolium chloride) staining was used to assess the infarct volume, TUNEL (Terminal deoxynucleotidyl transferase mediated dUTP nick end-labeling) to detect apoptotic cells, Western blots to evaluate protein level, and patch-clamp recordings to measure K(ATP) channel current activities. Behavioral tests were performed to assess the functional recovery after hypoxic-ischemic insults. We found that hypoxic preconditioning reduced infarct volume, decreased the number of TUNEL-positive cells, and improved neurobehavioral functional recovery in neonatal mice following hypoxic-ischemic insults. Pre-treatment with a K(ATP) channel blocker, tolbutamide, inhibited hypoxic preconditioning-induced neuroprotection and augmented neurodegeneration following hypoxic-ischemic injury. Pre-treatment with a K(ATP) channel opener, diazoxide, reduced infarct volume and mimicked hypoxic preconditioning-induced neuroprotection. Hypoxic preconditioning induced upregulation of the protein level of the Kir6.2 isoform and enhanced current activities of K(ATP) channels. Hypoxic preconditioning restored the HI-reduced PKC and pAkt levels, and reduced caspase-3 level, while tolbutamide inhibited the effects of hypoxic preconditioning. We conclude that K(ATP) channels are involved in hypoxic preconditioning-induced neuroprotection in neonatal hypoxic-ischemic brain injury. K(ATP) channel openers may therefore have therapeutic effects in neonatal hypoxic-ischemic brain injury.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
25448006
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"