Vardar, Selma ArzuAltun, Guelay DurmusGuenerbueyuek, CanerHatipoglu, Osman NuriMert, SelvaKaymak, Kadir2024-06-122024-06-1220060025-79311423-0356https://doi.org/10.1159/000088686https://hdl.handle.net/20.500.14551/22359Background: Most physiological measurements of the pulmonary diffusing capacity use carbon monoxide (CO) as a tracer gas. Similar to CO, melatonin binds the hemoglobin in the blood. Objective: The present study was designed to assess the effect of exogenous melatonin administration on pulmonary functions including diffusing capacity for carbon monoxide (DLCO) in healthy subjects. Methods: The study was performed in a randomized, double-blind, placebo-controlled manner. DLCO was measured in 22 healthy male volunteers ( age 18 - 25 years) who were randomized to melatonin (n = 11) and placebo administration ( n = 11). At baseline, DLCO, alveolar volume (V-A) and other spirometric parameters such as forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF) and maximal voluntary ventilation (MVV) were measured. DLCO was then corrected for the hemoglobin concentration. Measurements were repeated in a double-blind fashion 60 min after the administration of melatonin ( 1 mg) or placebo. Results: DLCO was significantly decreased (39.31 +/- 4.75 vs. 34.82 +/- 6.18 ml/min/mm Hg) 60 min after the melatonin administration ( p = 0.01), while FEV1, FVC, FEV1/FVC, PEF and MVV values did not demonstrate significant differences. Placebo administration did not result in significant alteration in any of these parameters. Conclusions: In healthy subjects, oral administration of melatonin acutely influences the DLCO without affecting other pulmonary function test results. We conclude that melatonin may have a reducing effect on the DLCO in the lungs. Copyright (C) 2006 S. Karger AG, Basel.en10.1159/000088686info:eu-repo/semantics/closedAccessMelatoninCarbon MonoxideDiffusing CapacityPulmonary FunctionPulmonary-FunctionBinding-SitesBloodVolumeRatesHeartArticle734509513Q3WOS:0002417755000182-s2.0-3374521251216195665Q1