TABLE 1.

Stability of endocannabinoids in blood, assessed by incubation of untreated, acidified, and inhibitor-treated (2.5 mM PMSF, 5 µM Orlistat) full-blood EDTA samples

Incubations were performed at 30°C (white fields) and on ice (gray fields). To quantify endogenous endocannabinoid levels, deuterated IS was spiked after plasma harvest (n = 3). To assess the stability of IS, EDTA blood was spiked prior to incubation (n = 2). Statistically significant differences at different time points relative to time point zero were tested with one-way ANOVA with repeated measures and Bonferroni´s post hoc correction. Samples with P < 0.05 are shown in a dashed box; those with P < 0.01 are highlighted in a full box.