Transection of the stria terminalis without damage to the medial amygdala does not alter behavioural sodium regulation in rats

Abstract

Damage to the medial region of the amygdala has been shown to impair mineralocorticoid-induced sodium appetite, while leaving intact sodium appetite induced through sodium depletion. This effect may result from the interruption of the flow of information through the stria terminalis (ST), a neural pathway linking the medial amygdala with the ventral forebrain. We determined the effect of transecting the ST of the rat, at a point remote from the medial amygdala, on sodium appetite induced with the administration of mineralocorticoids and with the natriuretic furosemide. Similar to control and amygdala lesioned rats, rats with ST knife-cuts displayed a normal sodium appetite following treatment with furosemide. However, unlike medial amygdala lesions, transection of the ST alone did not block mineralocorticoid-induced sodium appetite. Therefore, the inability of mineralocorticoids to induce a salt appetite in medial amygdala lesioned rats does not result from damage to the stria terminalis.