Neuropediatric Unit, Shaare Zedek Medical Center, Hebrew University, Jerusalem, Israel.
Sleep. 2012 Feb 1;35(2):187-91. doi: 10.5665/sleep.1618.
Hypocretin (orexin) is a unique neuropeptide involved in the consolidation of wakefulness and sleep. Although hypocretin-1 levels in the cerebrospinal fluid (CSF) are stable after infancy, how levels change in preterm and term human infants is unknown.
DESIGN, PATIENTS, AND SETTING: Hypocretin-1 levels were measured in CSF samples, obtained from 284 preterm (25-37 gestational weeks) and full-term infants in the first 4 months of life and 35 older children (ages 0.5-13 years), in a tertiary hospital.
Detailed clinical and laboratory data were collected for each of the 319 participants. Based on that data, 108 neurologically intact children were selected (95 infants [43 preterm and 52 term] and 13 older children). CSF hypocretin-1 was measured by direct radioimmunoassay. Hypocretin-1 levels at the first weeks of the 3rd embryonic trimester (gestational age [GA] 28-34 weeks) were 314 ± 65 pg/mL (n = 17). The levels linearly increased during the third trimester and early infancy (r = 0.6), peaking in infants of 2-4 months ages (476 ± 72 pg/mL; n = 16) and decreasing thereafter; hypocretin levels in 2- to 4-month-old infants were significantly higher than those in children 0.5-13 years old (353 ± 78 pg/mL, n = 13; P = 0.0001).
The present findings indicate that in human infants, CSF hypocretin-1 increases during the third embryonic trimester and is highest at 4 months of life. Thereafter, and consistent with previously published results, hypocretin levels are lower and stable until the geriatric age. This pattern may reflect the role of hypocretin in the dramatic process of sleep and wakefulness consolidation that occurs during early infancy.
食欲肽（orexin）是一种参与觉醒和睡眠巩固的独特神经肽。尽管脑脊液（CSF）中的食欲肽-1 水平在婴儿期后保持稳定，但早产儿和足月儿人类婴儿的水平如何变化尚不清楚。
设计、患者和环境：在一家三级医院，测量了 284 名早产儿（25-37 孕周）和足月儿婴儿在生命的前 4 个月以及 35 名年龄较大的儿童（0.5-13 岁）的 CSF 样本中的食欲肽-1 水平。
为 319 名参与者中的每一位都收集了详细的临床和实验室数据。基于这些数据，选择了 108 名神经完整的儿童（95 名婴儿[43 名早产儿和 52 名足月儿]和 13 名年龄较大的儿童）。通过直接放射免疫测定法测量 CSF 食欲肽-1。第 3 个胚胎期（孕龄 [GA] 28-34 周）的前几周的食欲肽-1 水平为 314 ± 65 pg/mL（n = 17）。水平在第三个三个月和婴儿早期呈线性增加（r = 0.6），在 2-4 个月龄的婴儿中达到峰值（476 ± 72 pg/mL；n = 16），此后下降；2-4 个月龄婴儿的食欲肽水平明显高于 0.5-13 岁儿童（353 ± 78 pg/mL，n = 13；P = 0.0001）。
本研究结果表明，在人类婴儿中，CSF 食欲肽-1 在第三个胚胎期增加，在 4 个月龄时达到最高。此后，与先前发表的结果一致，食欲肽水平较低且稳定，直到老年。这种模式可能反映了食欲肽在婴儿早期睡眠和觉醒巩固的剧烈过程中的作用。
