Quarterly Journal of Microscopical Science, Vol s3-98, 473-485, Copyright © 1957 by Company of Biologists

Some Aspects of the Structure and Cytology of the Gills of Lampetra fluviatilis

¹ Department of Zoology, The University, Nottingham

A description is given of the structure and vascularization of the lampern gill.

A comparison of the cellular components of the gill epithelium taken from lamperns at various stages of their spawning migration show that certain types of cells are common to all animals. These include the cells covering the gill platelets, the mucous cells, and certain basal cells from which others originate. The mucous cells are quite different in structure from those of teleosts.

There is a progressive loss of large acidophilic cells from certain regions of the gill filament as animals enter fresh water during the earlier stages of the spawning migration. These cells are similar in both structure and location to those described as chloride excretory cells from the gills of marine teleosts. They are typically large, flask-shaped cells with basal nuclei and they are filled with rod-shaped or spherical mitochondria. It is believed that they are responsible for the extra-renal excretion of monovalent ions during the process of marine osmoregulation in the lampern. The chloride excretory cells are very numerous in a limited number of fresh-run animals which are able to osmoregulate in 50% sea water.

In the normal course of events the chloride excretory cells are replaced by a smaller type of cell which is also rich in mitochondria, but unlike the excretory cells these lie at the surface of a transitional epithelium. It is argued that these cells may be responsible for ion uptake from fresh water in the maturing animal.

In male lamperns, large glandular cells of unknown function appear in the gill epithelium as the animal nears the time of spawning.