Circulating endogenous cannabinoid anandamide and portal, systemic and renal hemodynamics in cirrhosis

Abstract

Circulating levels of anandamide are increased in cirrhotic patients. However, this elevation was unrelated to the extent of arterial vasodilation, the severity of portal hypertension or the degree of hepatic and renal dysfunction. Although a local hormonal action cannot be excluded, our results do not support a relevant contribution of this system in the hemodynamic disturbance of cirrhosis.

A solid-phase method for the extraction and measurement of anandamide from multiple human biomatrices

“…The levels presented herein compare favourably with those previously published in non-pregnant volunteers (0.37 nM), by Fernandez-Rodriguez et al [22] and with those previously published by our group [13,17] for labouring women in two separate reports at term (2.5 nM, and 2.3 nM, respectively). The levels of AEA measured by both LPE and SPE methods in plasma from non-pregnant woman was 0.64 nM and 1.38 nM (range 0.51-3.99 nM) for term pregnant women.…”

Ultra performance liquid chromatography tandem mass spectrometry method for the measurement of anandamide in human plasma

“…When compared with the next fastest method, the run time employed here represents an improvement of over 4min/per injection previously for measurement of AEA [18]. Furthermore, this method represents a marked improvement in LOQ, LOD, precision and accuracy when compared with previously validated methods ( Table 2).…”

“…Measurements of endocannabinoids by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) in three recent studies in rat brain and human plasma have reduced analysis times to between 7-15 min. However, these studies have either a: not been validated [18], b: are used for brain tissues not plasma [19] or c: had comparatively poor limits of detection [20].…”

“…Although plasma AEA concentrations have been determined in a number of human cohorts, the mean AEA concentrations reported have varied considerably between studies, from 0.37 nM [18] and 2.58 nM [21] to 3.73 nM [20]. This 10-fold variability between studies suggests that plasma AEA concentrations can be difficult to determine routinely and thus a robust, validated analysis method is needed.…”

Release of anandamide from blood cells

“…Plasma concentrations of anandamide have been studied in a number of investigations (24)(25)(26)(27)(28)(29); interestingly, wide variations of mean plasma anandamide concentrations were reported in cohorts of healthy volunteers we.g., Fernandez-Rodriguez et al (27), mean anandamide concentration 0.13 mg/L; De Marchi et al (24), mean concentration 0.9 mg/Lx (conversion of units for anandamide: wnmol/Lx=0.35™wmg/Lx; wmg/Lx=2.87™wnmol/Lx). In these studies, reliable and accurate isotope dilution mass spectrometry methods were applied, but the authors gave no detailed information on preanalytical sample handling.…”