McCartney Christopher R, Prendergast Kathleen A, Blank Susan K, Helm Kristin D, Chhabra Sandhya, Marshall John C
Division of Endocrinology and Metabolism, Department of Medicine, Box 800391, University of Virginia Health System, Charlottesville, Virginia 22908, USA.
J Clin Endocrinol Metab. 2009 Jan;94(1):56-66. doi: 10.1210/jc.2008-1252. Epub 2008 Oct 28.
Peripubertal obesity (body mass index-for-age >or= 95%) in girls is associated with hyperandrogenemia. LH likely contributes to this relationship, but overnight LH secretion in obese girls is poorly characterized.
The aim of the study was to evaluate LH pulse characteristics in obese girls throughout pubertal maturation.
We conducted a cross-sectional analysis.
The study was performed in a general clinical research center.
Eight nonobese and five obese Tanner 1-2 girls participated, as well as 32 nonobese and 12 obese Tanner 3-5 girls.
Blood samples were collected every 10 min overnight (from 1900 to 0700 h).
LH pulse frequency, amplitude, and mean LH were measured in three 4-h time blocks (block 1, 1900-2300 h; block 2, 2300-0300 h; and block 3, 0300-0700 h).
Tanner stage 1-2 nonobese girls demonstrated nocturnal increases of LH frequency (P < 0.01, block 1 vs. 2) and mean LH (P < 0.05, block 1 vs. 2 and 3). Obese Tanner 1-2 girls had lower 12-h LH frequency and LH amplitude (P < 0.05 for both), with no overnight changes of LH pulse parameters. Compared to normal, LH frequency was elevated in Tanner 3-5 obese girls (P < 0.01 in all blocks), whereas LH amplitude was low (P < 0.05 in all blocks). Overnight increases of LH amplitude were observed in nonobese Tanner 3-5 girls (P < 0.0001), but not in obese Tanner 3-5 girls.
Obesity in prepubertal and early pubertal girls is associated with reduced LH secretion and reduced nocturnal changes of LH. In later pubertal girls, obesity is linked with reduced LH amplitude, but elevated LH frequency; the latter may reflect effects of hyperandrogenemia.
女孩青春期前肥胖（年龄别体重指数≥95%）与高雄激素血症有关。促黄体生成素（LH）可能与这种关系有关，但肥胖女孩的夜间LH分泌情况尚未得到充分描述。
本研究旨在评估肥胖女孩在整个青春期成熟过程中的LH脉冲特征。
我们进行了一项横断面分析。
该研究在一个综合临床研究中心进行。
8名非肥胖和5名肥胖的坦纳1-2期女孩，以及32名非肥胖和12名肥胖的坦纳3-5期女孩。
夜间每10分钟采集一次血样（从19:00至07:00）。
在三个4小时时间段（时间段1，19:00-23:00；时间段2，23:00-03:00；时间段3，03:00-07:00）测量LH脉冲频率、振幅和平均LH。
坦纳1-2期非肥胖女孩夜间LH频率增加（时间段1与2相比，P<0.01），平均LH增加（时间段1与2和3相比，P<0.05）。肥胖的坦纳1-2期女孩12小时LH频率和LH振幅较低（两者均P<0.05），LH脉冲参数夜间无变化。与正常情况相比，坦纳3-5期肥胖女孩的LH频率升高（所有时间段P<0.01），而LH振幅较低（所有时间段P<0.05）。非肥胖的坦纳3-5期女孩夜间LH振幅增加（P<0.0001），但肥胖的坦纳3-5期女孩没有。
青春期前和青春期早期女孩的肥胖与LH分泌减少和LH夜间变化减少有关。在青春期后期女孩中，肥胖与LH振幅降低但LH频率升高有关；后者可能反映了高雄激素血症的影响。
