Comparison of the effects of water deprivation and sodium chloride imbibition on the hormone content of the neurohypophysis of the rat.

1. Vasopressin and oxytocin have been measured in the neurohypophysis of rats which had either been given a 2% (w/v) NaCl solution to drink or been deprived of drinking water for up to 5 days.2. There was a progressive decrease in the vasopressin content of the glands in both groups; the rates of depletion were not significantly different.3. Oxytocin also decreased progressively in both groups but the glands from the ;saline-treated' rats contained less hormone than those from the ;water-deprived' animals.4. The differences in gland content of oxytocin could not be correlated with differences between the plasma osmolalities or sodium concentrations of the two groups.