Autophagy incidence is partially rescued by 10% FBS. (a) The incidence of autophagy annulus fibrosus (AF) cells after re-fed with 10% fetal bovine serum (FBS) for six hours. The cells were cultured in serum deprivation media with 10 ng/ml IL-1β for 24 hours to induce autophagy. Then the cells were re-fed with 10% FBS for six hours and the autophagy incidence was significantly decreased, whereas the apoptosis incidence showed no significant change, indicating that autophagy in the AF cells was rescued to some degree. All data are presented as the mean ± standard deviation (SD). *P < 0.01. (b) mRNA expression of autophagy-related genes in rat AF cells by real-time PCR analysis with or without serum supplementation. All data are presented as the mean ± SD. The mRNA levels of AF cells which were cultured in 10% FBS without IL-1β were used as controls. After re-fed with 10% FBS for six hours, the mRNA expression levels of Beclin-1 and microtubule associated protein 1 light chain 3 (LC3) decreased significantly. *P < 0.01.