For 21-days, the research team fed groups of male salt-resistant and salt-sensitive rats a diet containing either normal or high salt. Then they measured how the treatments influenced the animal's ability to excrete water and how the salt stress altered levels of vasopressin, G?從 and G?您.
The consumption of high salt triggered a decrease in G?從 proteins in the brain of salt-resistant, but not salt-sensitive, rats. In salt-sensitive rats, the team demonstrated that reducing brain G?從 proteins returned plasma vasopressin to normal levels, decreased salt-induced water retention, and restored the animal's ability to excrete water.
"Our findings are novel and provide evidence that the G?從 sub-unit proteins in the hypothalamus act as a molecular/cellular switch to control the level of vasopressin secretion," says Dr. Wainford.
The researchers concluded that reducing brain G?從 proteins plays a critical counter-regulatory role in preventing the secretion of too much vasopressin in those with salt-resistance and may represent a new therapeutic target in diseases associated with fluid retention.
Source: Louisiana State University Health Sciences Center