INFLUENCE OF THE NATURE OF THE HETEROATOM OF A MONOSACCHARIDE DERIVATIVE ON ITS INHIBITION OF TYPE-P CALCIUM CHANNELS EXPRESSED IN THE XENOPUS OOCYTE

Our results demonstrate that saccharidic derivatives obtained by addin g a C8 alkyl group through various heteroatomes (O, N or S) to a monoa cetonide residue possess an inhibitory effect towards putative P-type calcium channels expressed in Xenopus oocytes. These derivatives parti ally and reversibly inhibit the activity of these channels without cha nging their electrophysiological properties. Nevertheless, the derivat ive containing the heteroatome N also affects the fast and tetrodotoxi n-sensitive sodium channel activity. Thus, only ether and thioether co mpounds (heteroatome O or S) can be selected for their inhibitory effe ct on P-type apparented calcium channels.