Cadmium Induced Ultrastructural Changes in the Ciliate, Stylonychia Mytilus (ciliophora, Hypotrichida)

Transmission electron microscopy (TEM) revealed several ultrastructural changes induced by exposure to cadmium in ciliated protozoan, Stylonychia mytilus. The main cytoplasmic alterations in the post treated cells were:-condensation of the ground cytoplasm, mitochondrial disorganization, cytoplasmic vacuolization, accumulation of electron dense bodies and autophagosome formation. At the nuclear level, there was condensation of macronuclear chromatin and the nucleolar organization underwent major alteration. In the micronuclei, there was convolution of micronuclear surface and retraction of chromatin from the nuclear envelope. These modifications were compared with the changes induced by cisplatin, heat shock treatment, ageing and starvation.