Background:
The number of cancer survivors coincides with cardiovascular diseases is increasing, therefore, we are promoting the concept of “Onco-Hypertension” to clarify the mechanism linking cancer and blood pressure. In this study, we evaluated body osmolyte and water imbalance in hepatocellular cancer (HCC) model rats.
Methods:
Wistar rats were administered diethylnitrosamine (DEN) (1.5 μg/day, p.o.), a carcinogenic drug, for 8 weeks to establish liver cancer. Three weeks after the completion of DEN administration, we investigated blood pressure, tissue osmolyte and water content, and its association with aldosterone secretion.
Results:
HCC rats significantly reduced blood pressure, skin sodium, potassium, and water content. In the carcass (muscle + bone), dry weight, sodium, potassium, and water content were dramatically reduced without changing bone mass in HCC rats, suggesting that HCC causes muscle wasting to supply osmolyte and water for the dehydrated organs. These osmolytes and water loss were significantly associated with increased urinary aldosterone excretion. Supplementation of 0.25% salt water to drink improved body sodium and water loss and muscle wasting in HCC rats, which were completely suppressed by treatment with spironolactone (75 mg/kg/day, p.o.), a mineralocorticoid receptor (MR) blocker.
Conclusion:
These findings suggest that HCC causes body osmolyte and water loss, which leads to aldosterone hypersecretion and muscle catabolism to compensate for dehydration. A relatively small amount of salt supplement ameliorates the HCC-induced dehydration and muscle wasting via aldosterone/MR-mediated sodium and water restoration.
Cable parameters, sodium, potassium, chloride, and water content, and potassium efflux in isolated external intercostal muscle of normal volunteers and patients with myotonia congenita
