Zinc Regulation in the LobsterHomarus VulgarisI. Tissue Zinc and Copper Concentrations

Abstract

SUMMARY: Concentrations of Zn have been determined in the tissues of normal lobsters from sea water containing about 5μg/1. of Zn. The blood usually contains about 6 μg/g of Zn, mostly in the serum, while the soft tissues contain between 10 and 50 μg/g. Long exposure to sea water containing 100/μg.g/l. of Zn fails to alter the Zn concentrations of the blood, muscle and gonads, but increases the levels in the urine, excretory organs, hepatopancreas and gills. This result suggests that extra Zn is absorbed from high Zn sea water, possibly via the gills, and that two methods by which this is removed from circulation are by urinary excretion and absorption by the hepatopancreas.Changes in the blood Zn concentration produced by injection are rectified quite rapidly in the same way. Injections failed to change the Zn concentrations of muscle and gonads.Further experiments showed that Zn can be absorbed rapidly from the stomach and reaches the blood partly at least via the hepatopancreas. Again, this extra Zn is removed from the blood by urinary excretion and by absorption in the hepatopancreas. Eventual removal of Zn in the hepatopancreas probably takes place via the blood and excretory organs rather than via the gut. The role of the gills and gut in the regulation of the body Zn content has not yet been studied.