Chlordecone interaction of calmodulin binding with phosphodiesterase

Publisher Website
Google Scholar
Abstract
The effects of organochlorine (O.C.) compounds, such as aldrin, dieldrin, endrin, isodrin, chiordecone and mirex, on calmodulin (CaM) activity were investigated. Changes induced by O.C compounds on biological and physical properties of CaM were monitored in terms of phosphodiesterase stimulation and tyrosine fluorescence, respectively. None of the O.C. compounds altered tyrosine fluorescence of CaM in the presence of Ca2+. Except for chiordecone, none of the O.C. compounds inhibited CaM‐activated phosphodiesterase (PDE). Chlordecone significantly decreased (P > 0.05) CaM‐activated PDE in a concentration‐dependent manner without affecting the basal enzyme. Combination of chlordecone with W‐7 (CaM antagonist) increased the inhibitory effect of W‐7 on CaM activity. These results suggest that O.C. compounds may not be changing the tyrosine fluorescence of CaM. Among the O.C. compounds tested, chiordecone is a specific inhibitor of CaM‐activated PDE.