Acid phosphatase activity in the rat neurohypophysis during increased levels of gonadothrophic hormones, in diabetes insipidus (Bratteboro strain) and after water loading.

The acid phos phatase activity of the rat neurohypophysis was measured during increased gonadotrophic hormone levels, in diabetes insipidus (DI) (Brattleboro strain) and after water loading, i.e. conditions that interfere with the function of the hypothalamo-neurohypophyseal system (HNS). In addition determination of tissue protein, lipid and DNA and of water metabolism were performed. Neurohypophyseal acid phosphatase activity expressed on a dry weight basis increased under all conditions. For gonadectomized females, Brattleboro rats and water loaded males an increased water metabolism was observed. The increased acid phosphatase activity is interpreted as being related to disposal of release residues during stimulation of the HNS (increased gonadotrophic hormone levels and DI) and to disposal of neurosecretory material during inhibition (water loading).