Effect of serotonin receptor antagonists

Ketanserin (Sigma), an antagonist for 5HTR2A, was dissolved in 0.1 M HCl, diluted with PBS, and administered in a dosing volume of 0.1 mg/mouse. SB-204741 (Tocris Bioscience, Bristol, UK), an antagonist for 5HTR2B, was dissolved in DMSO, diluted with PBS such that the final concentration of DMSO was 0.1%, and administered in a dosing volume of 0.08 mg/mouse. SB-269970 (Sigma), 5HTR7 antagonist, and methysergide (Sigma), a 5HTR1, 2 and 7 antagonist, were dissolved in PBS and administered in a dosing volume of 0.6 and 0.1 mg/mouse, respectively. All antagonists were i.p. injected at 30 min before the injection of 1 mg 5-HT. After 120 min, samples were collected from skeletal muscle.