The Relaxant Effects of Propofol and Ketamine on Guinea-pig Tracheal Smooth Muscle.
10.4097/kjae.1997.32.2.185
- Author:
Ki Jun KIM
1
;
Shin Ok KOH
;
Won Oak KIM
;
Yong Taek NAM
Author Information
1. Department of Anesthesiology, Yonsei University College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Airway tracheal tone;
intravenous ketamine;
propofol;
guinea-pig;
smooth muscle
- MeSH:
Bronchial Spasm;
Carbachol;
Histamine;
Humans;
Ketamine*;
Muscle, Smooth*;
Propofol*
- From:Korean Journal of Anesthesiology
1997;32(2):185-191
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Propofol inhibits postoperative bronchospasm. Ketamine prevents bronchospasm in asthmatic patients. The present study was designed to evaluate the effects and mechanisms of propofol and ketamine on tracheal smooth muscles. METHODS: After isolating guinea-pig tracheal preparations, the maximal tracheal tones were induced by smooth muscle constrictors(2 10 7 M carbachol, 10 5 M histamine, 30 mM K+ Krebs solution, 124 mM K+ Krebs solution). When tracheal tones stabilized, propofol or ketamine was added cumulatively to obtain the concentration-relaxation curves, and calculated the ED50 and ED95. RESULTS: Propofol and ketamine decreased maximal tracheal tones in the concentration-dependent manners. The ED50 and ED95 of propofol were lowest in the histamine group, highest in the 30 mM K+ Krebs solution group. The ED50 and ED95 of ketamine were lowest in the 124 mM K+ Krebs solution group, highest in the histamine group. CONCLUSIONS: The relaxant effects of propofol and ketamine involve with all receptors in nonspecific way. However, propofol may inhibit more strongly the histamine mediated mechanism of tracheal contraction and ketamine may involve more strongly with Ca++ channel.
