Antibiotics cause changes in the desensitization of ACh receptors expressed in Xenopus oocytes.

ACh receptors (AChRs) synthesized in Xenopus oocytes which were cultured in medium containing gentamicin desensitized much more rapidly than those expressed in the absence of gentamicin. The effect caused by 24 h incubation in gentamicin could not be reversed by leaving oocytes in culture medium without gentamicin for 24 h. In addition, gentamicin exhibited a direct reversible blocking action on the function of AChRs. Our experiments indicate that antibiotics should be used cautiously in culturing oocytes when studying the function of induced neurotransmitter receptors and ion channels.