Heat shock proteins in human and mouse embryonic cells after exposure to heat shock or teratogenic agents.

In human chorionic villus tissue at the 10-17th week of a normal pregnancy, heat shock proteins (hsp70, hsp73, hsp85, and hsp105) were induced in vitro by a heat shock or by exposure to sodium arsenite or cadmium chloride. In dispersed cells of the whole mouse embryo on the 11th day of development, heat shock proteins (hsp73 and hsp105) were induced by a heat shock or by exposure to sodium arsenite, but not by exposure to cadmium chloride. After a maternal hyperthermia or an intraperitoneal injection of sodium arsenite or cadmium chloride into a pregnant mouse, heat shock proteins accumulated in the embryo on the 9th day of development, especially in the neuroepithelial tissue. The significance of heat shock proteins in the embryo is discussed.