PLASMA PROLACTIN LEVELS RELATED TO CHANGES OF SALINITY IN THE GREEN WATER FROG, RANA ESCULENTA

摘要

In this study the involvement of prolactin (PRL) in the adaptation to different salinities by the frog, Rana esculenta, has been studied. Two different populations of male frogs were investigated, one living at sea level in a lagoon in which the salinity varies in the range of 2 to 10 parts per thousand, and the other in a freshwater mountain pond. The results show that the values of plasma PRL are nor significantly higher in freshwater frogs than in those of the lagoon. Furthermore, an increase in salinity induces an increase of plasma PRL in freshwater frogs bur not in lagoon frogs.