Chen Zhuang-gui, Zhang Xue-hua, He Zheng-xian, Cai Yun
Department of Pediatrics, The Third Affiliated Hospital, Sun Yet-sen University, Guangzhou 510630, China.
Zhonghua Er Ke Za Zhi. 2004 Feb;42(2):121-4.
Leptin is an adipocyte-derived hormone regulating body weight and energy balance in animals and human being. Although the physiological functions of leptin in human are still unclear, its secretion is closely related to fat mass and energy expenditure in both adults and children. This study investigated whether the plasma leptin level was reduced in connection with the weight loss during the neonatal period and try to find out the role of leptin in body weight regulation and energy balance of premature infants.
The radioimmunoassay was used to determine the plasma leptin concentration. The first blood samples were obtained at the delivered, and then collected the samples every two days until the infants' body weight recovered to the birth weight or above. At the same time, the essential fluid and energy for the patients were supplied to keep their physiological functions. One person was appointed to take responsibility to examine the body weight, body length and head circumference. Then computed out their Kaup index from the first day to the seventh or twelfth day.
A total of 26 premature infants were selected into the study, of which 14 cases were male and 12 female, and their gestational age ranged from 30 to 36 weeks. There was a significantly positive correlation between the premature newborns' body weight loss and their plasma leptin levels (the 1st day: n = 26, r = 0.766; the 3rd day: n = 26, r = 0.636; the 5th day: n = 26, r = 0.629; the 7th day: n = 26, r = 0.717; the 9th-12th day: n = 24, r = 0.587; P < 0.01). The time of body weight loss and the plasma leptin level which declined to extremely low were positively correlated. (r = 0.611, P < 0.01). The time when body weight loss declined to extremely low in 26 premature infants ranged form the 3rd to the 9th day after birth [(5.2 +/- 1.6) day], and that of the plasma leptin levels ranged form the 3rd to the 8th day after birth (4.7 +/- 1.4) day. The maximal ranges of the body weight loss and the plasma leptin decrease in 26 premature infants were (6.5 +/- 3.0)% and (59.6 +/- 11.3)%, respectively. In addition, there were significantly positive correlations among the plasma leptin level, the premature newborns' body length (the 1st day: n = 26, r = 0.609, P < 0.01; the 3rd day: n = 26, r = 0.419, P < 0.05; the 5th day: n = 26, r = 0.583, P < 0.01; the 7th day: n = 26, r = 0.626, P < 0.01; the 9th-12th day: n = 24, r = 0.482; P < 0.05), and the Kaup index (the 1st day: n = 26, r = 0.634; the 3rd day: n = 26, r = 0.534; the 5th day: n = 26, r = 0.542; the 7th day: n = 26, r = 0.611; the 9th-12th day: n = 24, r = 0.539; P < 0.01). Although the head circumference correlated positively with the plasma leptin level at the first week after the delivery (the 1st day: n = 26, r = 0.580, P < 0.01; the 3rd day: n = 26, r = 0.417, P < 0.05; the 5th day: n = 26, r = 0.426; P < 0.01). There was a lower correlation between them one week after the delivery (the 7th day: n = 26, r = 0.369; the 9th-12th day: n = 24, r = 0.323; P > 0.05).
There was a significantly positive correlation between the plasma leptin level and the premature newborns weight loss. Leptin may participate in the regulation of energy balance and body weight of premature infants during neonatal life. Leptin may play an important role in growth and development of premature infants.
瘦素是一种由脂肪细胞分泌的激素，可调节动物和人体的体重及能量平衡。尽管瘦素在人体内的生理功能尚不清楚，但其分泌与成年人和儿童的脂肪量及能量消耗密切相关。本研究旨在探讨新生儿期体重减轻时血浆瘦素水平是否降低，并试图找出瘦素在早产儿体重调节和能量平衡中的作用。
采用放射免疫分析法测定血浆瘦素浓度。在婴儿出生时采集第一份血样，然后每两天采集一次血样，直至婴儿体重恢复到出生体重或以上。同时，为患者提供必需的液体和能量，以维持其生理功能。指定一人负责测量体重、身长和头围。然后计算出从第一天到第七天或第十二天的考普指数。
共纳入26例早产儿进行研究，其中男性14例，女性12例，胎龄为30至36周。早产新生儿体重减轻与其血浆瘦素水平之间存在显著正相关（第1天：n = 26，r = 0.766；第3天：n = 26，r = 0.636；第5天：n = 26，r = 0.629；第7天：n = 26，r = 0.717；第9 - 12天：n = 24，r = 0.587；P < 0.01）。体重减轻时间与降至极低水平的血浆瘦素水平呈正相关（r = 0.611，P < 0.01）。26例早产儿体重减轻降至极低水平的时间为出生后第3至9天[（5.2 ± 1.6）天]，血浆瘦素水平降至极低水平的时间为出生后第3至8天[（4.7 ± 1.4）天]。26例早产儿体重减轻的最大幅度和血浆瘦素降低的最大幅度分别为（6.5 ± 3.0）%和（59.6 ± 11.3）%。此外，血浆瘦素水平与早产新生儿身长之间存在显著正相关（第1天：n = 26，r = 0.609，P < 0.01；第3天：n = 26，r = 0.419，P < 0.05；第5天：n = 26，r = 0.583，P <
