title: Cadmium turnover in the hemocytes of Mercenaria mercenaria (L.) in relation to hemocyte turnover.
abstract: The turnover of cadmium (Cd) in the hemocytes of the quahog Mercenaria mercenaria L. was investigated using 109Cd radiolabeling, and compared to the rate of hemocyte turnover as estimated following [3H]thymidine incorporation. Quahogs were injected with 5 microl of 0.8 microM 109Cd, and the hemocytes sampled over a 60-day depuration period. Additional organisms were injected with 15 microl of 4.7 microM [3H]thymidine and radioactivity monitored over a 60-day period. Assuming that the loss of 3H from the hemocytes during the first 27 days of the experiment is due to hemocyte turnover, results indicate that Cd turnover rate (t 0.5 = 25.3 +/- 6.3 days) was similar to hemocyte turnover rate (t 0.5 = 28.5 +/- 14.3 days). This suggests that hemocytes retain Cd internally throughout their circulatory lifespan.
authors.affiliation: University of Massachusetts Boston, Department of Environmental, Coastal and Ocean Sciences, 02125-3393, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: McIntosh
authors.forename: W E
authors.initials: WE
authors.lastname: Robinson
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D002104:Cadmium / Q000493:pharmacokinetics*; D002106:Cadmium Radioisotopes / Q000493:pharmacokinetics; D002455:Cell Division; D006207:Half-Life; D006434:Hemocytes / Q000378:metabolism*
chemical_list: D002106:Cadmium Radioisotopes; D002104:Cadmium