Delayed effects of hypotensive drugs on structural characteristics of the renal glomerular system in hypertensive NISAG rats

Abstract

Comparative morphometrical study of the renal glomerular system was carried out in hypertensive NISAG rats treated with hypotensive drugs during the prepubertal period. Blockade of the renin-angiotensin system with enalapril or losartan during the critical period of ontogeny (the 2nd month of life) produced a long-term hypotensive and renoprotective effect. Treatment with alpha-adrenoblocker terazosin during this period of ontogeny produced a less pronounced hypotensive effect, though with renoprotection. Corinfar (Ca2+ channel blocker) was least effective.

Structural Characteristics of Renal Glomerular System in ISIAH Rats under Conditions of Chronic Stress and Preventive Hypotensive Drug Therapy

“…A trend to normalization of some major morphometric parameters was noted in the renal glomeruli of experimental rats treated with antihypertensive drugs (enalapril, losartan, or terazosin) during the prepubertal period and exposed to chronic stress, similarly as in rats under common conditions [1,3] (Table 1). The diameters of the renal glomeruli were smaller in rats treated with enalapril and terazosin, these values being intermediate between those in the controls and Wistar rats.…”

“…Importantly that the structural characteristics of the renal glomerular system, typical of each experimental group at rest [1][2][3], virtually did not change in stress.…”

“…The volume of basal membranes in the glomeruli of rats of these experimental groups was signifi cantly less than in control animals. We regarded these structural changes in the renal glomeruli, indicating reduction of signs of the glomerular fi lter dysfunction, as an evidence of the nephroprotective effect of preventive hypotensive therapy [1,3]. On the other hand, the renal glomeruli in all these animals retained to a certain measure the structure characteristic of the renal hypertensive status, for example, manifest mesangium or signs of podocyte hypertrophy (Fig.…”

“…An important problem (particularly in terms of prevention of hereditary arterial hypertension) is to attain a stable hypotensive effect after preventive antihypertensive therapy in early age. Our experiments on ISIAH hypertensive rats showed that enalapril or losartan blockade of the renin-angiotensin-aldosterone system (RAAS) during the 2nd month of life leads to a lasting (up to 4 months) reduction of BP and prevent the development of pathological changes in the renal glomerular system [1,3]. Experiments with terazosin (α-adrenoreceptor blocker) gives similar results, but only if the drug is injected during earlier age.…”