TY - JOUR
T1 - Clonidine enhances type-2 cationic amino acid transporter transcription in endotoxin-activated murine macrophages
AU - Lai, Yen Chun
AU - Tsai, Pei-Shan
AU - Huang, Chun Jen
N1 - Funding Information:
This work was supported by a grant from the National Science Council, Taiwan (NSC 93-2314-B-195-022) and a grant from Mackay Memorial Hospital (MMH 9415) awarded to Dr Chun-Jen Huang.
PY - 2008/9
Y1 - 2008/9
N2 - Background: We sought to evaluate the effects of clonidine on type-2 cationic amino acid transporter (CAT-2) transcription in endotoxin-activated murine macrophages. Methods: To determine the effects of clonidine on CAT-2 transcription, confluent murine macrophages (RAW264.7 cells) were treated with 1x phosphate buffered saline, clonidine (1000μM), lipopolysaccharide (LPS, 100ng/mL), or LPS plus clonidine (10, 100, or 1000μM). After reacting with LPS for 18 hours or a comparable duration in groups without LPS, cell cultures were harvested and the CAT-2 mRNA concentration was assayed. To determine the stability of CAT-2 mRNA, confluent macrophages were treated with LPS or LPS plus clonidine (100μM). After reacting with LPS for 6 hours, CAT-2 transcription was terminated and the stability of CAT-2 mRNA was determined. Results: The CAT-2 mRNA concentration of cell cultures receiving LPS plus clonidine (100μM) or LPS plus clonidine (1000μM) were significantly higher than that of the cell cultures receiving LPS alone, whereas the CAT-2 mRNA concentrations of cell cultures receiving LPS plus clonidine (10μM) was comparable to that of cell cultures receiving LPS alone. The data indicated that clonidine significantly enhanced LPS-induced CAT-2 transcription. The estimated half-life of CAT-2 mRNA of cell cultures receiving LPS was similar to that of cell cultures receiving LPS plus clonidine. These results indicated that clonidine did not affect CAT-2 mRNA stability. Conclusion: Clonidine enhances CAT-2 transcription in endotoxin-activated murine macrophages.
AB - Background: We sought to evaluate the effects of clonidine on type-2 cationic amino acid transporter (CAT-2) transcription in endotoxin-activated murine macrophages. Methods: To determine the effects of clonidine on CAT-2 transcription, confluent murine macrophages (RAW264.7 cells) were treated with 1x phosphate buffered saline, clonidine (1000μM), lipopolysaccharide (LPS, 100ng/mL), or LPS plus clonidine (10, 100, or 1000μM). After reacting with LPS for 18 hours or a comparable duration in groups without LPS, cell cultures were harvested and the CAT-2 mRNA concentration was assayed. To determine the stability of CAT-2 mRNA, confluent macrophages were treated with LPS or LPS plus clonidine (100μM). After reacting with LPS for 6 hours, CAT-2 transcription was terminated and the stability of CAT-2 mRNA was determined. Results: The CAT-2 mRNA concentration of cell cultures receiving LPS plus clonidine (100μM) or LPS plus clonidine (1000μM) were significantly higher than that of the cell cultures receiving LPS alone, whereas the CAT-2 mRNA concentrations of cell cultures receiving LPS plus clonidine (10μM) was comparable to that of cell cultures receiving LPS alone. The data indicated that clonidine significantly enhanced LPS-induced CAT-2 transcription. The estimated half-life of CAT-2 mRNA of cell cultures receiving LPS was similar to that of cell cultures receiving LPS plus clonidine. These results indicated that clonidine did not affect CAT-2 mRNA stability. Conclusion: Clonidine enhances CAT-2 transcription in endotoxin-activated murine macrophages.
KW - Cationic amino acid transporter 2
KW - Clonidine
KW - Macrophages
KW - Tipopolysaccharides
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U2 - 10.1016/S1875-4597(08)60005-3
DO - 10.1016/S1875-4597(08)60005-3
M3 - Article
C2 - 18809522
AN - SCOPUS:54449102118
SN - 1875-4597
VL - 46
SP - 118
EP - 123
JO - Acta Anaesthesiologica Taiwanica
JF - Acta Anaesthesiologica Taiwanica
IS - 3
ER -