In previous studies on gap junctional intercellular communication the authors indicated that magnetic field exposure at 0.8 mT had an inhibition effect on gap junctional intercellular communication (see "Related articles"). Meanwhile, the authors reported that an extremely low frequency magnetic field and/or TPA exposure decreased the quantity of non-phosphorylated connexin 43 and induced the appearance of a hyper-phosphorylated connexin 43, suggesting that the magnetic field and/or TPA could promote the connexin 43 phosphorylation (indicating that the inhibition of intercellular communication induced by the magnetic field may be due primarily to hyper-phosphorylation of gap junctional connexins).
CHL cells were exposed to 50 Hz sinusoidal magnetic field at 0.8 mT for 24 h without or with TPA (5 ng/ml).
Exposure duration: continuous for 24 h
Plasma membrane localized connexin 43 immunostained gap junctional plaques decreased after magnetic field exposure and/or TPA treatment while the number of connexin 43 in cytoplasm increased and congregated near the nuclei.
These findings indicate that reduction of connexin 43 at regions of intercellular contact may be one of the mechanisms of gap junctional intercellular communication inhibition induced by extremely low frequency magnetic fields.