Orexin-induced signalling and orexin receptor expression in heart samples from cardiac surgery patients
(A,B) In human heart tissue obtained from patients undergoing coronary artery bypass (n=8), both OR-A and OR-B showed no change in Akt phosphorylation compared with the non-treated heart tissue (100 nM). Change in the phosphorylation state was evident for ERK1/2 signalilng in the OR-B treatment group (*P<0.05 compared with control). (C) Expression of OX2R in heart samples from heart failure patients (n=54) demonstrated a significant decrease in OX2R in NYHA-II compared with NYHA-I patients (‡P<0.05) and in NYHA-III/IV compared with NYHA-II (*P<0.05) and to NYHA-I patients (†P<0.05) and NYHA-III/IV compared with NYHA-I (aP<0.05). NYHA: New York Heart Association Functional Classification for heart failure stages.