In vivo effect of Tulobuterol is examined the on the contractility of diaphragm muscles prepared from mice (BALBs/c mice; 21.7 ± 0.2 g) treated with Endotoxin. Contractile parameters of force-frequency curves and twitch kinetics using untreated or treated diaphragm muscles at 0 (E0) and 4 (E4) hours after E. coli endotoxin (20 mg/kg) administration are measured. E0 and E4 diaphragm muscles are analyzed at 0, 12, and 24 h after transdermal Tulobuterol treatment. The force-frequency curves of E0 and E4 diaphragm muscles at three time points are not significantly changed each other, indicating that Tulobuterol patch restores the muscle contractility. Thus, diaphragm muscle contractility is maintained during 4 h of endotoxin administration with Tulobuterol patch for over 24 h[2].