The Rectal Gland in Relation to the Osmoregulatory Mechanisms of Marine and Freshwater Elasmobranchs

Authors

Giuseppe Gerzeli, University of Pavia
Gian Franco de Stefano, University of Pavia
Lorenzo Bolognani, University of Milan
Kurt W. Koenig, Liceo Agricola de Granada
Maria Victoria Gervaso, University of Pavia
Maria Fausta Omodeo-Salé, University of Milan

Date of this Version

1976

Comments

Published in INVESTIGATIONS OF THE ICHTHYOFAUNA OF NICARAGUAN LAKES, ed. Thomas B. Thorson (University of Nebraska-Lincoln, 1976). Copyright © 1976 School of Life Sciences, University of Nebraska-Lincoln.

Abstract

The rectal gland of elasmobranchs secretes large quantities of electrolytes and is of primary importance in the osmoregulatory mechanisms of these animals (Burger and Hess, 1960; Burger, 1962). Analogously, various organs of other vertebrates are also known to be involved in salt secretion (Schmidt-Nielsen, 1965; Bonting, 1970; Bentley, 1971). In general, active ion transport is the basis of this phenomenon; in any case, it requires the presence of structural devices, morphologically and chemically well defined, and of metabolic capabilities which, taken singly, are not specific, but collectively are consistent with active ion transport and salt secretion.