Some observations on the fine structure of the sensory cells in the neuromasts (ordinary lateral line) of the teleost Gambusia affinis.

The structural and ultrastructural features of the sensory cells in the neuromasts of G. affinis were studied. These pear-shaped cels present a tuft of sensory hairs rising from the apex and a highly dense cytoplasm with multivesicular bodies, dyctiosomes, granular and smooth endoplasmic reticulum and numerous mitochondria. Large round granular dense bodies of an unknown nature can be observed inside and outside the nucleus. A great number of vesicles are present at the base of the cells, some of them associated with an afferent synapse, which also presents a presynaptic dense body. An efferent synapse with a nerve ending full of vesicles and a postsynaptic subsurface cisterna is also present at the base of these cells.