Desensitization of the pulmonary adenylyl cyclase system: a cause of airway hyperresponsiveness in congestive heart failure?
In heart failure, the down-regulation of pulmonary beta-receptors and concomitant decrease in adenylyl cyclase activity result in a significant attenuation of cAMP-mediated airway relaxation. These mechanisms may play a pivotal role in the pathogenesis of"cardiac asthma."
This study has not shown any excess risk among users of snuff for IHD or stroke. If there is a risk associated with snuff it is evidently much lower than those associated with smoking.