elemental imaging of thin freeze-dried cryosections from fresh cerebellar slices frozen within 20 sec of removal from the brain showed normal concentrations of potassium ( 95 +/- 6 mmol/liter wet tissue +/- sem ) and calcium ( 0.8 +/- 0.4 mmol/liter ) in whole presynaptic terminals , even though mitochondrial and nonmitochondrial sites containing up to 30 mmol of calcium per liter were present elsewhere in the neuropil .
C0006104
brain
C0086045
concentrations