Hypocretin-1 (Orexin-A) Levels in Human Lumbar CSF in Different Age Groups: Infants to Elderly Persons

Abstract

STUDY OBJECTIVES: Recent CSF and postmortem brain hypocretin measurements in human narcolepsy suggest that hypocretin deficiency is involved in the pathophysiology of the disease. In this study, we measured CSF hypocretin-1 levels in various age ranges from infants to elder people to investigate the age-dependent change of hypocretin concentrations. DESIGN: CSF hypocretin levels were compared by age groups and gender. ANOVA was used to examine the influences of these two parameters on CSF hypocretin levels. SETTING: University-based sleep and biology laboratory. PATIENTS OR PARTICIPANTS: Two hundred seventy two patients were included in this study, with 157 males and 115 females (0-79 years old). INTERVENTIONS: CSF samples were obtained by lumber punctures with informed consents. MEASUREMENTS AND RESULTS: Hypocretin-1 levels are not different in respect to gender or age, although our samples constitute a heterogeneous group with various disease conditions. CSF hypocretin-1 levels in infants under 4 months are similar to those in adults. CONCLUSIONS: Early maturation of hypocretin transmission is suggested. No age- or gender-dependent changes in CSF hypocretin is observed.