Ketamine and propofol in combination induce neuroapoptosis and down-regulate the expression of N-methyl-D-aspartate glutamate receptor NR2B subunit in rat forebrain culture.
OBJECTIVE
Ketamine has always been used in combination with propofol in paediatric patients. Ketamine interacts with N-methyl-D-aspartate glutamate receptor to exert its biologic actions. The NMDA receptor NR2B subunit is expressed at nearly adult level during forebrain development in the cortex and considered as the major type of functional NMDA receptor in the central nervous system. This study aimed to investigate whether ketamine or ketamine in combination with propofol induces apoptosis and regulates the expression level of NMDA receptor NR2B subunit in rat forebrain culture.


METHODS
Rat primary forebrain cultures were exposed to different concentrations of ketamine (1 microM, 10 microM, 20 microM) or 20 microM ketamine plus 5 microM propofol on the 6th day for 12 h. Cell viability was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Caspase-3 activity was measured and apoptotic morphology was examined by Hoechst dye staining. The expression of NMDA receptor NR2B subunit at mRNA and protein level was determined by qPCR and Western blot, respectively.


RESULTS
Ketamine (10 microM and 20 microM) or 20 microM ketamine plus 5 microM propofol resulted in a significant decrease in cell viability, and a significant increase in caspase-3 activity and apoptosis of primary rat forebrain culture. The expression of NMDA receptor NR2B subunit at both mRNA and protein levels were down-regulated by administration of ketamine (1 microM, 10 microM and 20 microM) and 20 microM ketamine plus 5 microM propofol.


CONCLUSIONS
Ketamine (10 microM or 20 microM) alone or in combination with propofol (20 microM ketamine plus 5 microM propofol) induces neuroapoptosis and down-regulates of NMDA receptor NR2B subunit in rat forebrain culture.
Department of Anaesthesiology, First Hospital, China Medical University, Shenyang, China.
Lidong
L
Fu
Rurong
R
Tang
Nairen
N
Bao
Junke
J
Wang
Hong
H
Ma
D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D018076:DNA, Complementary / Q000096:biosynthesis; D004357:Drug Synergism; D018691:Excitatory Amino Acid Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D007649:Ketamine / Q000008:administration & dosage / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects*; D009924:Organ Culture Techniques; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D016548:Prosencephalon / Q000378:metabolism*; D012313:RNA / Q000096:biosynthesis / Q000302:isolation & purification; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013778:Tetrazolium Salts; D013844:Thiazoles
D018686:Anesthetics, Intravenous; D018076:DNA, Complementary; D018691:Excitatory Amino Acid Antagonists; C121001:NR2B NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D013778:Tetrazolium Salts; D013844:Thiazoles; D012313:RNA; D007649:Ketamine; D053148:Caspase 3; C022616:thiazolyl blue; D015742:Propofol