Renal effects of goutweed preparations and metformin in rats receiving protamine sulphate and atherogenic diet

Abstract

It has been previously shown that the tincture and the extract obtained from Aegopodium podagraria L. can be favourably combined with metformin. This study aimed to evaluate the influence of the extract (1 g/kg), the tincture (1 ml/kg) and their combinations with metformin (50 mg/kg) on the excretory renal function in rats receiving the atherogenic diet combined with protamine sulfate during 15 days. The model was characterized by the decline in glomerular filtration rate (GFR) in water loading test, decrease in filtered load of sodium, its proximal and distal transport as well as excretion, the reduction of diuresis, potassium excretion, urine Na+ /K+ ratio. Metformin decreased creatininemia but led to the further decline in diuresis due to the enhancement in water reabsorption, proteinuria (but not protein excretion) was increased. Goutweed extract, per se and combined with metformin, enhanced water reabsorption, while GFR tended to the increase and diuresis remained unchanged. It normalized the filtered load of sodium and its proximal, but not distal, transport resulting in higher sodium excretion, significantly increased potassium excretion (urine Na+/K+ ratio remained reduced). Goutweed tincture normalized sodium and potassium excretion as well as urine Na+/K+ ratio, GFR, filtered load and proximal, but not distal, transport of sodium. Water reabsorption was unchanged, diuresis increased. After combined use of the tincture with metformin the renal effects of the latter, but not of the tincture were realized, antiproteinuric effect and minimal activity of alkaline phosphatase in plasma and urine were registered just in this group.