Albuterol-induced downregulation of Gsα accounts for pulmonary β₂-adrenoceptor desensitization in vivo
J. Clin. Invest. Paul A. Finney, et al. 106:125 doi:10.1172/JCI8374 [Go to this article.]

Figure 3
Effect of chronic treatment of rats with albuterol on albuterol-induced cAMP accumulation ex vivo. Rats were given saline (filled circles) or albuterol (open circles; 40 μg/kg/h) for 7 days, and the ability of albuterol to increase the cAMP content in lung was determined in the absence (a) or presence (b) of IBMX (100 μM). Each data point represents the mean ± SEM of eight determinations. Basal cAMP levels were 81 ± 75 and 57 ± 36 pmol/mg protein in saline- and albuterol-treated rats, respectively, in the absence of IBMX, and 803 ± 57 and 891 ± 78 pmol/mg protein in saline- and albuterol-treated rats, respectively, in the presence of IBMX. ^AP < 0.05, significant increase in cAMP formation induced by isoproterenol in IBMX-treated tissue.