The pars intermedia of the hypophysis during salt loading

Summary

Albino rats were subjected to the action of hypertonic NaCl solution for 20 days. Complete loss of neurosecretion in the pars posterior of hypophysis was noted. Basophilia of the cytoplasm of the majority of the pars intermedia cells increased exceedingly; the latter stained intensely with paraldehyde-fuchsin by Schiff-iodic acid method. Differentiation of intermedial cells into two types (differing structurally and tinctorially) was intensified. Formation of oxyphilic colloid (which is later resorbed) at the border of pars intermedia and anterior is characteristic of the early experimental periods; at the same time cytoplasmic basophilia of the cells of the first type in the pars intermedia is reduced, whereas by the end of the experiment it is seen to increase markedly. The changes observed demonstrate the relationship between the pars intermedia function and the humoral effects of the neurohypophysis.