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Published on: July 3, 2013
Biphasic manner of melittin on isolated guinea pig atria
1Department of Pharmacology, School of Pharmacy, Shanghai Medical University, Shanghai 200032, China. mhjiang@shmu.edu.cn
Aim:
To investigate the effect of melittin (Mel) on isolated guinea pig atria.
Methods:
The effect of Mel on the contraction and heart rate of isolated guinea pig atria at different concentrations was determined.
Results:
Mel at a lower concentration (0.1-0.8 mumol.L-1) enhanced the contraction of left atria in a concentration-dependent manner; but at a higher concentration (1.6-12.8 mumol.L-1) it exerted an inhibitory effect. At 0.1-30 mumol.L-1 it was found to increase heart rate of right atria. In addition, verapamil (Ver) 0.3 mumol.L-1 was found to depress the effect of Mel.
Conclusion:
Mel possesses a biphasic effect on left atria and a positive chronotropic effect on right atria. Its mechanism might be related with Ca2+ channel.
