RESUMO
Objective To evaluate the effect of dexmedetomidine on Toll-like receptor 4 ( TLR4)/myeloid differentiation factor 88 ( MyD88)/nuclear factor Kappa B ( NF-κB) signaling pathway in the pe-ripheral blood mononuclear cells of elderly patients with diabetes mellitus undergoing lower extremity surger-y. Methods Forty elderly patients of both sexes with type 2 diabetes mellitus, aged 65-80 yr, with body mass index of 18. 5-27. 9 kg/m2 , of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, with New York Heart Association Ⅰ or Ⅱ, undergoing lower extremity surgery with tourniquets under general anesthesia, were divided into 2 groups ( n=20 each) by using a random number table method: control group ( group C) and dexmedetomidine group ( group D) . Combined intravenous-inhalational anesthesia was applied. Dexmedetomidine was infused over 15 min in a dose of 1μg/kg after induction of anesthesia, fol-lowed by a continuous infusion of 0. 5 μg·kg-1 ·h-1 until the end of surgery in group D, while the equal volume of normal saline was given instead of dexmedetomidine in group C. Before using the the tourniquet and at 15 min, 1 h and 24 h after loosing the tourniquet, arterial blood samples were collected for determi-nation of the expression of TLR4, NF-κB and MyD88 in peripheral blood mononuclear cells and concentra-tions of tumor necrosis factor-alpha ( TNF-α) , interleukin-1β ( IL-1β) , cardiac troponin I ( cTnI ) and creatine kinase-MB ( CK-MB) in plasma. Results Compared with group C, the expression of TLR4, NF-κB and MyD88 in peripheral blood mononuclear cells was significantly down-regulated, and the concentra-tions of TNF-α, IL-1β, cTnI and CK-MB in plasma were decreased at each time point after loosing the tourniquet in group D ( P＜0. 05) . Conclusion The mechanism by which dexmedetomidine reduces myo-cardial damage may be related to inhibiting TLR4/MyD88/NF-κB signaling pathway and reducing systemic inflammatory responses in elderly patients with diabetes mellitus undergoing lower extremity surgery.
RESUMO
Objective To establish a cell line with overexpression of rat serotonin1A receptor (5-HT1AR).Methods Human neuroblastoma cells-SH-SY5Y were donated by cancer institute attached to the 4 th Affiliated Hospital, Hebei Medical University. Total RNA was extracted from brain tissues of male SD rats and rat 5-HT1A R was obtained by RT-PCR. Plasmid pc-DNA3. 1/hisC containing the rat 5-HT1AR (pc-DNA3.1/hisC-Rat-5-HT1AR)was constructed and transfected into SH-SY5Y cells. The transfected cells were isolated by G418 selection and SH-SY5Y-Rat-5-HT1A R cells were obtained. Expression of 5-HT1A R was detected by Western blot analysis. Cell viability was evaluated by MTT assay. SH-SY5Y-Rat-5-HT1AR cells were further observed for 5-HT1AR by immuno-fluorescence staining. Results Plasmid pc-DNA3. 1/hisC-Rat-5-HT1AR was successfully constructed by linking Rat-5-HT1A R with pc-DNA3.1/hisC and transfected into SH-SY5Y. The SH-SY5Y-Rat-5-HT1A R cells were more slender than SH-SY5Y cells with less and longer processes. MTT showed that the viability of SH-SY5Y-Rat-5-HT1A R cells was much lower than SH-SY5Y. Rat 5-HT1A R was expressed efficiently on the membrane of SH-SY5Y-Rat-5-HT1A R cells. Conclusion A cell line with overexpress of rat 5-HT1A R is successfully established.