Resumen

FERNANDEZ, Carmen et al. Renal handling of ß2 microglobulin: Its significance in carriers of adolescent nephronophthisis (NPH3). Invest. clín [online]. 2007, vol.48, n.2, pp.139-145. ISSN 0535-5133.

The adolescent nephronophthisis (NPH3) is a variant of the nephronophthisis. In Venezuela, one to three patients have been registered each year, all of them belonging to the same family tree. The objective of this study was to evaluate the function of the proximal convoluted tubule in NPHP3 carriers; using the ß2M as biological marker. Eight carriers, 7 heterozygotes and l homozygote, with normal renal function were compared with a 10 healthy subjects (control group). Serum ß2 microglobulin (ß2M), urinary ß2M, the quocient urinary ß2M/urinary creatinine and the ß2M fractional excretion were determinated. The filtered ß2M and the percentage of reabsortion were calculated. We observed an increase in the plasmatic concentration of ß2M but not related with a decrease of the glomerular filtration. The urinary ß2M, the ß2M/urinary creatinine relation and the fractional excretion of ß2M were normal. The filtered load of ß2M was elevated without increase in the excretion or percentage of reabsortion. We conclude that in our group of NPH3 carriers, functional changes in the proximal convoluted tubule, when measured by urinary excretion of ß2M, were absent. This finding suggests the existence of other mechanism of uptake or degradation of the substance in the proximal convoluted tubule, which have yet to be elucidated.

Palabras clave : Adolescent nephronophthisis; proximal convoluted tubule; ß2 microglobulin.

        · resumen en Español     · texto en Español     · Español ( pdf )