[Interstitial cells and the antihypertensive function of the renal medulla].

The role of the interstitial cells (IC) in the hypotensive function of the renal medulla is demonstrated by their direct participation in the synthesis of renal prostaglandins (PG), which permanently control the excretion of sodium and water. The medullar PG deficiency, caused by either low or inadequate to the sodium load PG synthesis, has negative effect on the renal hemodynamics, vascular resistance and the excretion of sodium and water. These factors are important at a certain stage of arterial hypertension development. Arterial hypertension is the factor, stimulating the hypotensive function of IC. The stimulating effect of hypertension on IC may result in both their hyperfunction (in regard to the production of the depressor PG) and their hyperplasia and proliferation. The effect of hypertension on the medullar IC can be mediated through the changes of the local environmental water-electrolyte parameters. Therefore the function of IC is closely related to the renal medullar function on the whole and first of all to the concentration function of its vessels and tubules.