Small doses of DCA administered at intervals in pellet form are capable of raising the blood pressure, altering renal function, and changing the electrolyte pattern in the intact rat. The concomitant feeding of 1 per cent saline intensifies the process.
The elevation in blood pressure occurs prior to demonstrable changes in renal excretory function.
The alteration in renal function consists first of a reduction in CPAH with the maintenance of a normal filtration rate. Filtration fraction is elevated while there is no reduction in renal plasma flow per unit of tubular excretory tissue. Later, filtration is interfered with and renal ischemia occurs.
The electrolyte change is characterized by a sustained fall in plasma K and Cl, a rise in plasma Na, an increase in the Na/Cl ratio, and finally an elevation of Na plus K. Plasma Ca is unaffected.
These observations suggest the possible etiological significance of the adrenal cortex in some types of hypertension.