铁、锌、铅对学龄儿童生长激素分泌的影响

目的研究7～17岁儿童生长激素分泌水平,并探讨血清铁、血清锌和血铅含量对生长激素分泌的影响。方法采取分层整群抽样对济宁市744名7～17岁青少年儿童,空腹采集静脉血5ml,运用放射免疫法测定血清生长激素含量,分光光度法测定血清铁含量,电位溶出法测定血清锌和全血中铅的含量。结果男、女童生长激素分泌的突增年龄分别为11岁和9岁;9～10岁年龄段女童分泌量显著高于男童,12岁以后男童分泌水平反超女童;随着血清铁含量的增加,生长激素分泌量呈逐渐增大趋势,低、中、高3个血清铁含量组生长激素分泌量差异有统计学意义（F=18.78,P〈0.05）;锌充足组生长激素分泌量高于缺乏组,差异有统计学意义（t=9.338,P〈0.01）;随着血铅含量增加,生长激素分泌水平逐渐降低,经方差分析显示：相对安全组、超标组和高铅组生长激素分泌量差异有统计学意义（F=6.68,P〈0.05）。结论女童生长激素分泌的突增期早于男童;血清中铁、锌含量的增加能促进生长激素的分泌,血铅的增加则抑制生长激素的分泌。

The Effect of Iron, Zinc and Lead on the Production of Secretion of Growth Hormone in School Children

Objective To study the effect of iron, zinc and lead on growth hormone secretion level of children aged 7-17 years. Methods 744 children aged 7-17 years were randomly selected by stratified cluster sampling in Jining, and with empty stomach 5 ml venous blood was drawn to measure the content of growth hormone through Radio-Immunoassay, the content of serum iron through spectrophotometry, and serum zinc and whole blood lead content through Potentiometric Stripping Analysis. Results The growth hormone secretion overshoot periods for boys and girls are respectively around age 11 and age 9. Secretion is much higher in girls than in boys from age 9 to 10, while after the age of 12, secretion level in boys overtakes that in girls. Following the increase of iron in the blood, growth hormone secretion is also rising; the differences in growth hormone secretion between low, medium and high serum iron groups have statistical significance （F=18.78, P〈0.05）; zinc sufficiency group has a significant higher growth hormone secretion than the deficiency group （t=9.338, P〈0.01）; as the content of blood lead increases, growth hormone secretion level falls, variance analysis showing a statistic significance（F=6.68, P〈0.05） differences in the growth hormone secretion between relatively safe level group, the over standard level group and the high level group. Conclusion Girls＇ growth hormone secretion overshoot period is earlier than boys＇; the increase of iron and zinc in blood serum can promote growth hormone secretion, while the increase of blood lead restrains growth hormone secretion.