Related Experiment Video
Updated: May 20, 2026

High-Throughput Small Molecule Drug Screening For Age-Related Sleep Disorders Using Drosophila melanogaster
Published on: October 20, 2023
Serotonin and melatonin secretion and metabolism in patients with liver cirrhosis
Cezary Chojnacki1, Ewa Walecka-Kapica, Grażyna Klupińska
1Department of Gastroenterology, Medical University of Lodz, Łódź, Poland.
Introduction:
Hepatic encephalopathy is one of the symptoms of liver failure. The exact causes of encephalopathy are complex and still unclear. Apart from elevated blood ammonia levels, the role of numerous other factors is being considered.
Objectives:
The aim of the study was to determine the serum level of serotonin and melatonin and the urinary excretion of their metabolites (5-hydroxyindoleacetic acid [5-HIAA] and 6-sulfatoxymelatonin [6-HMS]) in patients with various stages of liver cirrhosis.
Patients And Methods:
The study comprised 75 patients with alcohol-induced liver cirrhosis and 25 healthy subjects (control group). Based on the Child-Pugh classification, 3 groups of 25 patients each were distinguished - group A, B, and C with grade A, B, and C of liver failure, respectively. Blood samples were drawn at fasting at 9 a.m., and 24-hour urine collection was performed. Immunoenzymatic assays were used to determine serum melatonin and serotonin levels as well as urine 5-HIAA and 6-HMS concentrations.
Results:
Serum serotonin levels were 159.8 ± 23.1 ng/ml in controls, 179.3 ± 21.1 ng/ml in group A (P >0.05), 143.2 ± 22.8 ng/ml in group B (P >0.05), and 114.5 ± 37.6 ng/ml in group C (P <0.01). Serum melatonin levels were 10.6 ± 1.7 in controls, 31.2 ± 9.8 pg/ml in group A (P <0.01), 49.8 ± 12.2 pg/ml in group B (P <0.001), and 94.8 ± 22.6 pg/ml in group C (P <0.001). Urinary 5-HIAA excretion was 5.9 ± 2.1 mg/24 h in controls, 5.9 ± 1.9 mg/24 h in group A (P >0.05), 4.8 ± 1.2 mg/24 h in group B (P >0.05), and 4.6 ± 1.4 mg/24 h in group C (P <0.05). Urinary 6-HMS excretion was 26.6 ± 15.1 μg/24 h in controls, 23.2 ± 7.9 μg/24 h in group A (P >0.05), 18.3 ± 10.6 μg/24 h in group B (P >0.05), and 6.5 ± 3.6 μg/24 h in group C (P <0.001).
Conclusions:
Disturbances in serotonin and melatonin homeostasis observed in patients with liver cirrhosis may be associated with advanced encopaholopathy.
Related Concept Videos
Management of Insomnia
Sedatives and Hypnotics Drugs: Miscellaneous Agents
Melatonin congeners like ramelteon (Rozerem) and tasimelteon (Hetlioz) selectively bind to melatonin receptors (MT1 and MT2) and thus mimic the actions of melatonin, a hormone that regulates sleep-wake cycles. Tasimelteon is primarily used for non-24-hour sleep-wake disorder, common in blind patients. They are also used to treat conditions like insomnia...
Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test
Major Hormones and Their Functions
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
Factors Affecting Drug Biotransformation: Biological
Species differences: Variations in enzyme systems across species can cause disparities in drug metabolism. For instance, humans may metabolize certain drugs faster than rodents, altering therapeutic effects.
Strain differences: Genetic variations within a species can result in differing enzyme activity, impacting drug response and toxicity. For example, some mouse strains may...
Circadian Rhythms and Gene Regulation

