Probing of specific binding of synthetic sulfonylurea with the insulinoma cell line MIN6.

ABSTRACT

To overcome the limitation of conventional sulfonylurea (SU) for investigation of biological mechanisms related to KATP channels, a hypoglycemic sulfonylurea (SU) was conjugated with a non-reducing glucose bearing polystyrene (PS) derivative to provide enhanced interaction with an insulinoma cell line (MIN6). The specific interaction between the SU (K+ channel closer)-conjugated copolymer and MIN6 cells was confirmed by confocal laser microscopic images using rhodamine B isothiocyanate (RITC)-labeled SU-conjugated polymer, which revealed the specific interaction between SU-conjugated polymer and MIN6 cells. Moreover, the location of labeled polymer and the site of Ca2+ ion mobilization obtained from the same MIN6 cells were identical. Based on the specificity and insulinotropic activity, the SU-conjugated polymer is expected to be useful tool for the study of biological mechanisms of KATP channels.