Histology and Cytochemistry of the Neurosecretory Cells (NSC) of the Freshwater Snail Lymnaea luteola (Lamarck) Mollusca: Gastropoda

Four types of neurosecretory (NS) cells are noticed in the cerebral, pleural, buccal and pedal ganglion of the freshwater snail Lymnaea luteola. According to the size and staining properties they are classified as A, B, C and D type cells. These are giant cells, medium cells, small cells and smallest cells. Type ‘A’ cells are largest of the all cells and measures about 0.0600-0.0800 mm in diameter. The B cells are smaller than ‘A’ cells and are ranges from 0.035-0.040 mm in diameter. The ‘C’ and ‘D’ cells are smaller than the ‘A’ and ‘B ‘cells and more or less oval in shape. The histochemical observations reveal that the neurosecretory material is rich in carbohydrates, disulphides, sulfhydryl group, protein bound amino groups, glycoprotein and lipids.