Biochemical and hormonal changes induced by one week of administration of rIGF-I to patients with Laron type dwarfism.

Summary. objective The purpose of this investigation was to evaluate the effectiveness of short-term administration of recombipant bfosynthetfc IGF-I on patients with an hereditary inability to generate this hormone. design and patients Ten patients with Laron type dwarfism (LTD) (4 males, six females) aged 3° to 37° years were submitted to seven daily s.c. Injections of recombinant IGF-I in doses of 120 or 150 μg/kg/day. measurements Blood samples were drawn before, after three and seven Injections, and one week after stopping the trial. results The main biochemical and hormonal changes registered were (mean ± SD): a marked rise in serum type III procollagen (PIHNP) from 4.2±0.9 to 7.3.2 μg/l (P < 0.0003) and decrease in the following blood components: plasma hGH from 32.51±43.77 to 4.02±2.48 mU/I (P < 0.001), serum cholesterol from 5.9±1 to 5.7±0.8 mmol/l (P < 0.04), serum SGOT from 28.9±11.6 to 15.5±7.6 U/I (P < 0.01) and serum LDH from 286.88 to 222.37 U/I (P 0.0005). The response of plasma insulin was variable, decreasing in seven of ten and Increasing in three. Some of these effects were transitory, and were found after 3 days therapy but afterwards decreased (insulin, cholesterol and liver tests), others persisted throughout the whole treatment period (hGH, PIIINP). conclusions IGF-I mlmics the biochemical and hormonal changes described after administration of hGH. The administration of IGF-I In patients with Laron type dwarfism is devoid of side-effects and warrants assessment in long-term studies.