Differential gene expression induced by growth hormone treatment in the uremic rat growth plate

Treatment with growth hormone (GH) improves growth retardation of chronic renal failure. cDNA microarrays were used to investigate GH-induced modifications in gene expression in the tibial growth plate of young rats.

RNA was extracted from the tibial growth plate from two groups, untreated and treated with GH, of young rats made uremic by subtotal nephrectomy (n=10). To validate changes shown by the Agilent oligo microarrays, some modulated genes known to play a physiological role in growth plate metabolism were analyzed by real-time quantitative polymerase chain reaction (qPCR).

The microarrays showed that GH modified the expression of 224 genes, 195 being upregulated and 29 downregulated. qPCR results confirmed the sense of expression change found in the arrays for insulin-like growth factor I, insulin-like growth factor II, collagen V alpha 1, bone morphogenetic protein 3 and proteoglycan type II.

This study shows for the first time the profile of growth plate gene expression modifications caused by GH treatment in experimental uremia and provides a basis to further investigate selected individual genes with potential implication in the stimulating effect on the growth of GH treatment in chronic renal failure.