THE SUBCELLULAR-DISTRIBUTION OF CALCIUM IN THE VISUAL CELLS OF CRAYFISH, OBSERVED WITH THE COMBINED OXALATE-PYROANTIMONATE TECHNIQUE, DEPENDS ON EXTRACELLULAR CALCIUM
H. Jarminowski et H. Stieve, THE SUBCELLULAR-DISTRIBUTION OF CALCIUM IN THE VISUAL CELLS OF CRAYFISH, OBSERVED WITH THE COMBINED OXALATE-PYROANTIMONATE TECHNIQUE, DEPENDS ON EXTRACELLULAR CALCIUM, Zeitschrift fur Naturforschung. C, A journal of biosciences, 50(7-8), 1995, pp. 581-587
1. With the combined oxalate-pyroantimonate method we determined the s
ubcellular distribution of calcium in the photoreceptor cells of the c
rayfish Orconectes limosus. 2. The calcium antimonate deposits were id
entified with the electron microscope. Energy-dispersion X-ray analysi
s verified that the electron dense deposits contained calcium and anti
mony. 3. Calcium antimonate deposits were found in the submicrovillar
cisternae, mitochondria, multivesicular bodies, and pigment granules,
as well as in the cytoplasm. 4. The calcium deposits in the cytoplasm
of the retinula cell and in the pigment granules were reduced after in
cubation of the retinae in a solution with a lowered calcium concentra
tion and even more after we permeabilized the plasma membrane with the
saponin beta-escin. 5. We suppose that the calcium-storing pigment gr
anules participate in the regulation of the cytosolic calcium concentr
ation of the crayfish photoreceptor cells.