LPS and IL‐1α increase endogenous morphine production in mollusk Mytilus edulis pedal ganglia

Abstract

We have found that morphine and its metabolite, morphine‐6‐glucuronide, are endogenously produced in the ganglionic tissue of the marine mollusk Mytilus edulis. Stress, such as cold and starvation, appears to regulate the production of these opiate alkaloids. In order to determine which signals can trigger the release and possible synthesis of morphine in the mussel, we incubated dissected ganglia with lipopolysaccharide (LPS) and interleukin one alpha (IL‐1α). Using solid phase extraction, HPLC, RIA and mass spectrometry, we have found both compounds are able to increase morphine production at the micromole level. At 24 h post incubation, morphine reaches its highest level for LPS (42.63 ± 3.81 ng/mL) and IL‐1α (31.57 ± 6.24 ng/mL) respectly. These results are comparable to the data found in rats.