TY - JOUR
T1 - Metabolic and genetic analyses of apoptosis in potassium/serum-deprived rat cerebellar granule cells
AU - Miller, Timothy M.
AU - Johnson, Eugene M.
PY - 1996/12/1
Y1 - 1996/12/1
N2 - Cerebellar granule cells maintained in medium containing serum and 25 mM potassium undergo an apoptotic death within 96 hr when switched to serum- free medium with 5 mM potassium. Because large numbers of apparently homogeneous neurons can be obtained, this represents a potentially useful model of neuronal programmed cell death (PCD). Analysis of the time course and extent of death after removal of either serum or K alone demonstrated that a fast-dying (T( 1/4 ) = 4 hr) population (20%) responded to serum deprivation, whereas a slow-dying (T( 1/4 ) = 25 hr) population (80%) died in response to K+ deprivation. Taking advantage of the complete death after removing both K+ and serum, changes in metabolic events and mRNA levels were analyzed in this model. Glucose uptake, protein synthesis, and RNA synthesis fell to <35% of control by 9 hr after potassium/serum deprivation, a time when 85% of the cells were still viable. The pattern of the fall in these metabolic parameters was similar to that reported for trophic factor-deprived sympathetic neurons. Most mRNAs decreased markedly after K+/serum deprivation. Levels of c-jun mRNA increased fivefold in potassium/serum- deprived granule cells; c-jun is required for cell death of sympathetic neurons. mRNA levels of cyclin D1, c-myb, collagenase, and transin remained relatively constant in potassium/serum-deprived granule cells. These data demonstrate the existence of two populations of granule cells with respect to cell death and define common metabolic and genetic events involved in neuronal PCD.
AB - Cerebellar granule cells maintained in medium containing serum and 25 mM potassium undergo an apoptotic death within 96 hr when switched to serum- free medium with 5 mM potassium. Because large numbers of apparently homogeneous neurons can be obtained, this represents a potentially useful model of neuronal programmed cell death (PCD). Analysis of the time course and extent of death after removal of either serum or K alone demonstrated that a fast-dying (T( 1/4 ) = 4 hr) population (20%) responded to serum deprivation, whereas a slow-dying (T( 1/4 ) = 25 hr) population (80%) died in response to K+ deprivation. Taking advantage of the complete death after removing both K+ and serum, changes in metabolic events and mRNA levels were analyzed in this model. Glucose uptake, protein synthesis, and RNA synthesis fell to <35% of control by 9 hr after potassium/serum deprivation, a time when 85% of the cells were still viable. The pattern of the fall in these metabolic parameters was similar to that reported for trophic factor-deprived sympathetic neurons. Most mRNAs decreased markedly after K+/serum deprivation. Levels of c-jun mRNA increased fivefold in potassium/serum- deprived granule cells; c-jun is required for cell death of sympathetic neurons. mRNA levels of cyclin D1, c-myb, collagenase, and transin remained relatively constant in potassium/serum-deprived granule cells. These data demonstrate the existence of two populations of granule cells with respect to cell death and define common metabolic and genetic events involved in neuronal PCD.
KW - RNA synthesis
KW - c-jun
KW - chronic depolarization
KW - glucose uptake
KW - protein synthesis
UR - http://www.scopus.com/inward/record.url?scp=0029909560&partnerID=8YFLogxK
U2 - 10.1523/jneurosci.16-23-07487.1996
DO - 10.1523/jneurosci.16-23-07487.1996
M3 - Article
C2 - 8922404
AN - SCOPUS:0029909560
SN - 0270-6474
VL - 16
SP - 7487
EP - 7495
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 23
ER -