Dense-granule secretion assay.

<p>(<b>A</b>) Platelets isolated from mice after 24 hours of 5-HT infusion exhibit increased dense-granule exocytosis, as indicated by increased levels of secreted 5-HT. Dense granule secretion was monitored by measuring the level of fluorescent material which was created by OPT as described in the Materials and Method section. The measurements were done at excitation wavelength 355 nm and emission wavelength 475 nm. Data represent mean ± SD; Asterisk (*) indicates statistical significance compared to Saline+SLO by Student’s <i>t</i>-test, <i>p<0.05</i>. (<b>B</b>) Dense-granule secretion was monitored following plasma membrane staining for granulophysin (CD63), a surrogate marker of exocytosis. FACS analysis demonstrates increased mean fluorescence intensity following 5-HT infusion compared to saline-infused littermates.