Effects of caffeine withdrawal on isoproterenol-stimulated cyclic adenosine monophosphate

The effect of short-term caffeine withdrawal on lymphocyte beta-adrenoceptor sensitivity was studied in seven men who had been drinking coffee daily for at least 3 mo before the study. The ratio of cyclic adenosine monophosphate production after in vitro incubation with isoproterenol and a blank was used to assess receptor sensitivity. There was a reduction in sensitivity to isoproterenol but not to prostaglandin E1 3 days after caffeine withdrawal. The mechanism of this effect is not clear, but may represent a biochemical correlate of caffeine-withdrawal syndrome.