Industrial depuration may provide a means of removing domoic acid toxin from blue mussels (Mytilus edulis). Mussels containing up to 50 μg domoic acid∙g−1 were transported from a Prince Edward Island estuary into controlled laboratory conditions to test the effects of temperature, salinity, mussel size, and feeding upon depuration. Fifty percent of toxin was eliminated within 24 h. After 72 h, mussels were either clean or contained, on average, only residual levels of toxin (< 5 μg∙g−1), regardless of conditions. Exponential depuration curves were fitted to the domoic acid concentration data. To evaluate differences in rate of depuration under various conditions, statistical comparisons were made between slopes of the clearance curves. Rates of depuration were faster in small (45–55 mm) than in large mussels (60–70 mm) and more rapid at 11 than at 6 °C. There was no significant difference in depuration rate at 18‰ salinity as opposed to 28‰ or in starved versus fed mussels. Because of their relatively large digestive glands, meats of small mussels contained more toxin per unit weight than meats of large mussels. The bulk of domoic acid appeared to reside in the gut lumen. However, the presence of small amounts of domoic acid in intracellular compartments cannot be ruled out.

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Tappia, Paramjit S., Mohinder S. Nijjar, Aric Mahay, Nina Aroutiounova, and Naranjan S. Dhalla. Phospholipid profile of developing heart of rats exposed to low-protein diet in pregnancy. Am J Physiol Regul Integr Comp Physiol 289: R1400 -R1406, 2005. First published July 14, 2005; doi:10.1152/ajpregu.00319.2005Although the myocardial phospholipid and fatty acid content have profound effects on the heart function, very little information is available on the effects of restricted maternal protein intake during pregnancy on the phospholipid profile and fatty acid content of the developing heart. The present study was therefore undertaken to examine the effect of pregnant dams fed diets containing either 180 (normal) or 90 (low) g/kg casein diet for 2 wk before mating and throughout pregnancy on myocardial phospholipid and fatty acid content of male offspring. Whereas no changes in phosphatidylcholine and phosphatidylethanolamine were detected, increases in lysophosphatidylcholine, phosphatidylserine, and sphingomyelin were seen in the hearts of offspring in the low-protein (LP) group. Analysis of cardiac fatty acids revealed that although the saturated fatty acid (myristate, palmitate, and stearate) levels were significantly reduced, the unsaturated fatty acid (linoleate, arachidonate, and decosahexanoate) levels were significantly increased in the developing heart in the LP group. Furthermore, assessment of nuclear transcription factors involved in regulation of cardiac metabolism revealed a decrease in myocyte enhancer factor-2C mRNA levels in the LP group, whereas an increase in the mRNA amount of peroxisome proliferator-activated receptor-␣ was observed in this group. These results demonstrate that maternal LP diet can induce changes in the phospholipid profile and fatty acid content of the developing heart, which may have implications for metabolism of the neonatal heart. maternal low-protein diet; fatty acids; energy metabolism THE ENVIRONMENTAL EXPERIENCE of the growing fetus influences the development of specific organs, including the heart (6). We have recently reported that a maternal low-protein (LP) diet induces a severe depression of the contractile function of the neonatal heart (6); however, nothing is known about the mechanisms responsible for this effect. Cardiac phospholipids are known to be organized into functionally differentiated domains (32) and provide both structural integrity and a suitable microenvironment for the normal functioning of membrane proteins (32). Furthermore, polyunsaturated fatty acids (PUFAs), which are important structural and functional components of cell membrane phospholipids, are also required to support normal growth and development and are critical for normal cell function (1,16,23,25,30). The metabolic machinery of the heart is designed to allow many different substrates to be used for ATP synthesis (3), which is required for normal cardiac function. The change in substrate preference during normal maturation from glucose (10,12,(27)(28)(29)31) and lactate to fatty ...