A copolymer of N-isopropylacrylamide (98 mole% in the feed) and acrylic acid poly(N-isopropylacrylamide-co-acrylic acid) [p(NiPAAm-co-AAc)], and the adhesion molecule, an Arg-Gly-Asp (RGD)-incorporated hydrogel, were used to entrap pheochromocytoma cells (PC12). In a 28-d culture period, the PC12 cells in the RGD-conjugated gel maintained higher viability and produced dopamine at constant rates, while there was lower cell viability and less dopamine secretion by PC12 cells in p(NiPAAm-co-AAc). PC12 cells cultured in the RGD-conjugated gel would constitute a potentially useful three-dimensional cell system for application in nerve regeneration.