Effects of the somatostatin analogue octreotide on renal function in conscious diabetic rats

Background. Studies performed during the last decade have indicated that growth hormone (GH) and insulinlike growth factors (IGFs) may mediate the early renal changes in diabetes mellitus. i.e. hypertrophy and hyperfiltration. This and other observations have led to the suggestion that GH/IGF inhibitors, such as long-acting somatostatin analogue (e.g. octreotide and lanreotide), may be useful in order to inhibit or prevent development of long-term diabetic complications. Methods. The present study examined the acute and chronic effects or octreotide on renal function following induction of streptozotocin (STZ)-diabetes in rats. The studies were carried out in conscious. non-fasted diabetic animals. Results. Chronic administration of octreotide for 7 days, from onset of diabetes, prevented the decrease of effective renal vascular resistance (ERVR), and the increases in filtration fraction (FF). glomerular filtration rate (GFR), and absolute proximal tubular fluid reabsorption (APR) induced by diabetes. The renal hypertrophy was only partially prevented. In the acute study, similar changes were observed in effective renal plasma flow (ERPF) and ERVR but FF increased and GFR remained unaltered. Conclusions. Chronic but not acute treatment with octreotide prevented the renal hyperfiltration caused by diabetes. This effect is most likely due to an increase in afferent arteriolar resistance.