Activity-dependent accumulation of calcium in Purkinje cell dendritic spines

Journal Article · Tue Mar 01 00:00:00 EST 1988 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.85.5.1682· OSTI ID:5243815

Andrews, S B; Leapman, R D; Landis, D M; Reese, T S

The calcium content of synapses of parallel fibers on Purkinje cell dendritic spines was determined by electron probe x-ray microanalysis of freeze-dried cryosections from directly frozen slices of mouse cerebellar cortex. In fresh slices frozen within 20-30 sec of excision, calcium concentrations ranging from 0.8 to 18.6 mmol/kg of dry weight were measured in cisterns of smooth endoplasmic reticulum within Purkinje cell dendritic spines. The average calcium content of spine cisterns in rapidly excised slices (6.7 +/- 0.6 mmol/kg of dry weight +/- SEM) was higher than the average calcium content of spine cisterns in brain slices incubated without stimulation for 1-2 hr before direct freezing (2.5 +/- 0.4 mmol/kg of dry weight). Depolarization of incubated cerebellar slices by isotonic 55 mM KCl resulted in the accumulation within spine cisterns of very high amounts of calcium or isotonically substituted strontium, both derived from the extracellular fluid. These results suggest that one function of spine cisterns is to sequester free calcium that enters the spine through ligand-gated or voltage-gated channels during synaptic transmission.

• Research Organization: National Institute of Neurological and Communicative Disorders and Stroke, Bethesda, MD (USA)
• OSTI ID: 5243815
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 85:5
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALCIUM
BIOLOGICAL ACCUMULATION
DENDRITES
CHEMICAL COMPOSITION
BIOELECTRICITY
CEREBELLUM
ELECTRON MICROPROBE ANALYSIS
ENDOPLASMIC RETICULUM
FREEZING
MICE
POTASSIUM
ALKALI METALS
ALKALINE EARTH METALS
ANIMALS
BODY
BRAIN
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
CHEMICAL ANALYSIS
CRYSTALS
ELECTRICITY
ELEMENTS
MAMMALS
METALS
MICROANALYSIS
NERVOUS SYSTEM
ORGANOIDS
ORGANS
RODENTS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques