Possible Interaction: Aldosterone and Oxytocin

“The increase in WR frequency induced by elevated plasma osmolality was augmented by injection of aldosterone or angiotensin-I. In vivo water uptake, measured in a water bath, was increased by an NaCl or oxytocin injection, but not by aldosterone.”

“In conclusion, we have shown that concomitant administration of aldosterone and oxytocin increased the rate of excretion of Na+ in two different preparations, which supports the idea of an interaction between the steroid and oxytocin to promote Na+ loss.”

“The possibility of an interaction between oxytocin and aldosterone to influence renal Na+ excretion was investigated in Inactin‐anaesthetized male Sprague‐Dawley rats.”

“… aldosterone … oxytocin was associated with a significantly (P < 0.01) increased Na+ excretion rate from a peak pretreatment value of 6.8 +/− 0.7 mumol/min … value of 11.5 +/− 1.1 mumol/min by 1 h 40 min after the start of treatment in Adx rats (n = 7).”

“ Oxytocin enhances the effects of aldosterone in blood from intact...”

“The sodium retaining activity of 0.5 and 1.0 µg of aldosterone was abolished when used in combination with 2.5 and 5.0 mu oxytocin.”

“Lower doses of aldosterone are needed if oxytocin is injected simultaneously.”

“Besides showing that oxytocin affects the output of electrolytes by a mechanism different from renin, these experiments would appear to support the assumption that oxytocin enhances the elimination of sodium by counteracting the effect of aldosterone.”

“It has been shown that a dose range of 2.5–5 mu of oxytocin neutralizes the sodium-retaining activity of 1 µg of aldosterone2.”