Changes in calcium distribution in the utricular supporting cells of the guinea pig.

Changes in calcium distribution in cultured utricular supporting cells following streptomycin sulfate (SM) intoxication were investigated by means of an organ culture system using potassium pyroantimonate (PA) precipitation. PA precipitation showed that calcium ions are located in the otoconia and in the secretory granules of the supporting cells. Exposure of the supporting cells to SM increased the number of lysosomes and reduced the secretory granules in the cytoplasm. These lysosomes had many granules containing calcium ion. It is suggested that calcium secretion from the secretory granules was inhibited by SM and that this might lead to reduction of otoconia.