ion; (2) the stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) pathway, which is activated in response to stresses such as heat, high osmolarity, UV irradiation, and proinflammatory cytokines such as tumor necrosis factor????? and interleukin-1 (IL-1); and (3) the p38 pathway, which is responsive to osmotic stress, heat shock, lipopolysaccharide, tumor necrosis factor?????, and IL