Influence of tris(4-chlorophenyl)methanol (TCPM) on gap junction-mediated intercellular communication of cultured bovine granulosa cells.
Tris(4-chlorophenyl)methanol (TCPM) is a by-product in the manufacture of technical grade DDT, which is known to alter properties and functions of the female reproductive system. We investigated whether in vitro TCPM has an influence on the function of gap junction-mediated intercellular communication (GJIC) and gap junction protein expression of connexin 43 (Cx43) in cultured bovine granulosa cells. GJIC was assessed by fluorescent dye microinjection (dye-coupling). After a 1-h exposure to TCPM at a concentration of 32 microM, a significant (P<0.05) reduction in dye coupling occurred. The same result was obtained with o,p'-DDT. At a concentration of 32 microM both pesticides were cytotoxic as indicated by significant (P<0.05) increased propidium iodide staining of the cell nuclei. Little or no effect on the stainable pattern of connexons occurred after 1 h incubation time, while after 3 h treatment from 16 to 64 microM TCPM, a significant inhibition in the immunostaining resulted and the concentrations of 32 and 64 microM TCPM were cytotoxic for the granulosa cells. The freeze-fracture electron microscopy resulted in small differences in the morphology of gap junction plaques of cell cultures treated for 3 h with 8 or 16 microM TCPM in comparison to untreated cells. After treatment with 32 microM TCPM, gap junction plaques were very rarely detected and the lateral intramembraneous particles (IMP) distribution of many plasma membranes was strongly altered. Estimation of the cellular parameters may lead to an enhanced understanding of the mechanism of chemically induced toxicity by TCPM, that causes a general toxic effect on granulosa cells. We can conclude that TCPM is a toxic risk in the same manner as DDT.
Tiemann
U
U
Department of Reproductive Biology of the Research Institute for the Biology of Farm Animals, Dummerstorf, Germany. tiemann@fbn-dummerstorf.de
Pöhland
R
R
Richter
W
W
Wollenhaupt
K
K
D000818:Animals; D002417:Cattle; D002450:Cell Communication / Q000187:drug effects*; D002466:Cell Nucleolus / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D002478:Cells, Cultured; D018031:Connexin 43 / Q000378:metabolism; D003634:DDT / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005614:Freeze Fracturing; D017629:Gap Junctions / Q000187:drug effects* / Q000648:ultrastructure; D006107:Granulosa Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D007306:Insecticides / Q000494:pharmacology; D014320:Triphenylmethyl Compounds / Q000633:toxicity*
D018031:Connexin 43; D007306:Insecticides; D014320:Triphenylmethyl Compounds; C104274:tris(4-chlorophenyl)methanol; D003634:DDT; C016340:o,p'-DDT