title: [Changes of endoplasmic reticulum stress- and apoptosis-related factors in rat cerebral cortex following controlled hypotension].
abstract: OBJECTIVE
  To investigate the changes of endoplasmic reticulum stress (ERS)- and apoptosis-related factors in rat cerebral cortex following controlled hypotension.
  
  
  METHODS
  Twenty-four healthy male SD rats were randomly divided into 4 equal groups, including a sham hypotension group (group A) and 3 hypotension groups with the mean arterial pressure maintained for 60 min at 70 mmHg (group B), 50 mmHg (group) and 30 mmHg (group D) with sodium nitroprusside and esmolol. All the rats received an equal volume of fluid infusion. Twelve hours after controlled hypotension, the rats were sacrificed to examine the protein expressions of Bax, Bcl-2, glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and caspase-12 in the cortex with Western blotting. GRP78 mRNA expression was measured by RT-PCR, and the cell apoptosis was evaluated by TUNEL staining.
  
  
  RESULTS
  Compared with those in group A, GRP78 mRNA and protein expressions of GRP78, CHOP, caspase-12 related with ERS increased significantly in groups C and D (P<0.05), especially in group D (P<0.05), but not in group B (P>0.05). Apoptotic cells and Bax expression increased and Bcl-2 expression decreased significantly in groups C and D (P<0.05), but not in group B (P>0.05); such changes were more prominent in group D than in group C (P<0.05).
  
  
  CONCLUSIONS
  Mild controlled hypotension (70 mmHg) does not induce neuronal injury in rat cerebral cortex, but severe hypertension (lower than 50 mmHg) can cause neuronal ERS and apoptosis.
authors.affiliation: Department of Anesthesiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China.E-mail: jianxingzhang_edu@163.com.
authors.forename: Jianxing
authors.initials: J
authors.lastname: Zhang
authors.forename: Hongying
authors.initials: H
authors.lastname: Li
authors.forename: Guobin
authors.initials: G
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D002540:Cerebral Cortex / Q000473:pathology*; D059865:Endoplasmic Reticulum Stress; D007023:Hypotension, Controlled; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D051017:Apoptosis Regulatory Proteins