PMID- 19080567
OWN - NLM
STAT- MEDLINE
DCOM- 20100909
LR  - 20161124
IS  - 1001-0939 (Print)
IS  - 1001-0939 (Linking)
VI  - 31
IP  - 9
DP  - 2008 Sep
TI  - [Carotid body inflammation and carotid sinus nerve afferent activity after 
      intermittent hypoxia exposure of various frequencies in rabbits].
PG  - 670-4
AB  - OBJECTIVE: To explore the inflammatory reactions, endothelin level and carotid 
      sinus nerve (CSN) afferent activity of carotid body (CB) after intermittent 
      hypoxia/reoxygenation (IH/ROX) exposure of various frequencies in rabbits. 
      METHODS: Forty-nine male adult New Zealand white rabbits (2.5-3.0 kg) were 
      separated into 7 groups (n = 7 each). After anesthetization, the right carotid 
      artery and CSN were cleared of surrounding tissues without touching the right CB 
      and the left carotid region. The CSN was unenveloped to partially expose the 
      myelin sheath, and electrodes were placed to the "single" chemoreceptor bundle of 
      the CSN, with CSN afferent activity carefully monitored and recorded. Then the 
      right common carotid artery was exposed, cannulated to distal part and its 
      proximal part was ligated. Preparations were challenged by changing the PO2 of 
      the gas mixture equilibrating the perfusate. Alternatively perfusion (2 ml/min) 
      of equilibrated perfusate bubbled with normoxia or hypoxia gas mixtures formed 
      IH/ROX cycles in right carotid common artery, simulating the pattern of hypoxic 
      episodes seen in obstructive sleep apnea, or with continuously perfusing hypoxia 
      perfusate to form continuous hypoxia (CH) modes. Groups were defined with 
      different frequencies, and groups were: intermittent normoxia group (IN group) 
      (21% O2, 15 s; 21% O2, 1 min 45 s), 10/hr group (5% O2, 15 s; 21% O2, 5 min 45 
      s), 30/hr group (5% O2, 15 s; 21% O2, 1 min 45 s), 50/hr group (5% O2, 15 s; 21% 
      O2, 57 s), 60/hr group (5% O2, 15 s; 21% O2, 45 s) and 90/hr group (5% O2, 15 s; 
      21% O2, 25 s). All the above groups were exposed to 60 treatment cycles; 
      continuous hypoxia group (CH group), IN for 1 h 45 min and then 5% O2 for 15 min. 
      After exposure and 30 min of static placing, CSN afferent frequencies (Charge F) 
      were recorded from chemoreceptor bundles, and the right CB was cleared of 
      surrounding tissues and harvested. Interleukin-6 (IL-6), endothelin-1 (ET-1), 
      hypoxia-inducible factor-1 (HIF-1), and vascular endothelial growth factor (VEGF) 
      concentrations of the CB lysate were measured with enzyme linked immuno sorbent 
      assay (ELISA) kits and standardized. Data were analyzed with SPSS 12.0 software 
      package; and after one way analysis of variance (ANOVA) for whole difference, 
      Tamhane's T2 was used for post hoc analysis. RESULTS: IL-6, ET-1 and Charge F 
      increased but then decreased with increasing IH frequencies (F = 25,601.39, 
      2390.48, 6945.84, all P values < 0.01). IL-6, ET-1 and Charge F levels in 50/hr 
      group were the highest among groups. Charge F levels correlated significantly 
      with IL-6 or ET-1 (with IL-6: r = 0.736, P < 0.01; with ET-1: r = 0.757, P < 
      0.01, respectively). IL-6, ET-1 and Charge F levels between IN group and CH group 
      were not statistically different (all P values > 0.05). HIF-1 levels elevated 
      gradually (F = 5241.10, P < 0.01) with increasing exposure frequencies, and the 
      CH group had the highest value (all P values < 0.01). VEGF level in CH group was 
      the highest in all groups (all P values < 0.01). CONCLUSIONS: After IH/ROX 
      exposure, afferent activity of CB CSN increases, which significantly correlates 
      with inflammation and vasomotor mechanism of CB. CB inflammation comes not from 
      IH phases but from ROX phases. Increased CB CSN activity results in elevated SNA 
      tension, which plays a key role in the pathogenesis of systemic hypertension. 
      This procedure influenced by IH/ROX frequencies. CH for 15 min causes no 
      definitely damages. However, HIF-1 and VEGF can be considered as members of 
      adaptive pathway during IH/ROX exposure.
FAU - Feng, Jing
AU  - Feng J
AD  - Respiratory Department of Tianjin Medical University General Hospital, Tianjin 
      300052, China.
FAU - Chen, Bao-yuan
AU  - Chen BY
FAU - Cui, Lin-yang
AU  - Cui LY
FAU - Wang, Bao-li
AU  - Wang BL
FAU - Liu, Chun-xia
AU  - Liu CX
FAU - Chen, Pan-feng
AU  - Chen PF
FAU - Guo, Mei-nan
AU  - Guo MN
FAU - Dong, Li-xia
AU  - Dong LX
FAU - Li, Shuo
AU  - Li S
LA  - chi
PT  - Journal Article
PL  - China
TA  - Zhonghua Jie He He Hu Xi Za Zhi
JT  - Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal 
      of tuberculosis and respiratory diseases
JID - 8712226
SB  - IM
MH  - Afferent Pathways/*metabolism
MH  - Animals
MH  - Carotid Body/*pathology
MH  - Carotid Sinus/innervation
MH  - Hypoxia/*metabolism/*pathology
MH  - *Inflammation
MH  - Male
MH  - Rabbits
EDAT- 2008/12/17 09:00
MHDA- 2010/09/10 06:00
CRDT- 2008/12/17 09:00
PHST- 2008/12/17 09:00 [entrez]
PHST- 2008/12/17 09:00 [pubmed]
PHST- 2010/09/10 06:00 [medline]
PST - ppublish
SO  - Zhonghua Jie He He Hu Xi Za Zhi. 2008 Sep;31(9):670-4.