Expression of pulmonary vasoactive factors after sevoflurane anaesthesia in rats: a quantitative real-time polymerase chain reaction study.
BACKGROUND
Sevoflurane is a fluorinated volatile anaesthetic agent that lowers arterial pressure, in part by vasodilation. We previously showed, in rat lungs, that sevoflurane affected the expression of endothelin-1 (ET-1), a potent vasoconstrictor peptide. Therefore, we hypothesized that the vasodilation induced by sevoflurane involved vasodilatory and vasoconstrictor components.


METHODS
Rats were anaesthetized with sevoflurane 4% for 0, 2, and 6 h (n=9 each group) before death. In addition, a further group (n=9) were anaesthetized for 6 h then awoken for 2 h before death (n=9). We measured expression of mRNA encoding ET-1, nitric oxide synthase-1, 2, 3 (NOS1, 2, 3), haeme oxygenase-1, 2 (HO-1, 2), adrenomedullin (ADM), calcitonin gene-related peptide, vasoactive intestinal peptide, and prostacyclin synthase in whole lung using real-time reverse transcriptase-polymerase chain reaction.


RESULTS
Expressions of ET-1 and ADM were significantly increased by inhalation of sevoflurane for 2 and 6 h (P<0.05). Expression of NOS3 was significantly increased at 6 h (P<0.05). After awaking from anaesthesia, the expressions of NOS3, ET-1, and ADM returned to baseline levels.


CONCLUSIONS
Sevoflurane increased the expressions of ET-1, NOS3, and ADM. Our results suggest that the increased expressions of NOS3 and ADM may counteract that of ET-1 and so regulate pulmonary circulation under sevoflurane anaesthesia.
Takemori
K
K
Department of Anaesthesiology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603, Japan. kt2ndnmsmeb@hotmail.com
Kobayashi
K
K
Sakamoto
A
A
D053607:Adrenomedullin / Q000096:biosynthesis / Q000235:genetics; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D019332:Endothelin-1 / Q000096:biosynthesis / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics; D011652:Pulmonary Circulation / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D000077149:Sevoflurane; D014664:Vasodilation / Q000187:drug effects* / Q000502:physiology
D018685:Anesthetics, Inhalation; D019332:Endothelin-1; D008738:Methyl Ethers; D053607:Adrenomedullin; D000077149:Sevoflurane; D019001:Nitric Oxide Synthase