Dietary sodium concentration modifies catecholamine release with stress in spontaneously hypertensive rats

A high sodium diet increased the plasma norepinephrine (PNE) only in resting spontaneously hypertensive rats (SHR). SHR on either a high or low sodium diet showed a greater increase in arterial pressure (AP) than Wistar-Kyoto rats (WKY) with foot shock (FS). However, neither a high nor low sodium diet enhanced the increment of AP in both SHR and WKY with FS. Only a low sodium diet enhanced the increment of PNE and plasma epinephrine in SHR with FS. Extreme restriction of sodium intake might thus enhance the response of sympathetic activation with stressful stimuli.