Fig. 6.

Cyclic nucleotide levels. Cyclic nucleotide concentrations were measured in lysed washed platelets from fresh PB samples and from stored RT-APC or C-APC. After extraction with diethyl ether the contents of cGMP ( A ) and cAMP ( B ) were determined with immunoassays. Results are presented as mean (fold stimulation) ± SEM; n  = 4; * p  < 0.05, ^# p  < 0.1 (compared as indicated; blue: RT-APC to C-APC; n.s.: not significant). APC, apheresis-derived platelet concentrates; cAMP, cyclic adenosine monophosphate; C-APC, cold-stored apheresis-derived platelet concentrates; cGMP, cyclic guanosine monophosphate; DEA/NO, diethylamine NONOate; PB, peripheral blood; PGE1, prostaglandin E1; RT, room temperature; SEM, standard error of mean.