Patofizjiologiczne i komórkowe mechanizmy prenatalnego upośledzenia nefrogenezy w nefropatii zaporowej - następstwa i implikacje kliniczne

Congenital obstructive nephropathy is one of the most common causes of renal insufficiency in children. In the study, current knowledge on molecular phenomena occurring in fetal kidney is presented, under circumstances of urinary retention. Normal kidney development is related to the increase of the number of nephrons. Vasculature is maturing with regressive renin activity along afferent arterioles and its localization in juxtaglomerular apparatus. Maturation of glomeruli is characterized by proliferation of vascular bundle and its coverage by podocytes. Maturation of tubules consists in disappearance of vimentine and increasing expression of EGF. Fibroblasts of the interstitium loose their expression of α actinine of the smooth muscles and vimentine. The consequence of the retention in the kidney is inhibition or suppression of normal maturation. In addition to obstructive nephropathy, retention induces enhanced production of oxygen radicals, angiotensin and TGF β 1 and stimulates tubular apoptosis leading to tubular atrophy and fibrosis of the interstitium. Urinary retention during the period of organogenesis suppresses, and sometimes “reverses” the proceeding molecular processes, enhancing cell differentiation and apoptosis. Impairment of the kidney development is proportional to the period and degree of retention. It is accompanied by compensatory hypertrophy of the other kidney. Diagnostics and prenatal therapy promise to inhibit the destruction of the kidney before surgical restoration of urinary tract patency.