Year: 1989
Type: article
Study design: Observational Study
Abstract: To determine whether a diurnal rhythm exists in neonates admitted to neonatal intensive care units where there is continuous artificial lighting and periodic nursing and medical care, plasma cortisol, adrenocorticotropin (ACTH), and beta-endorphin concentrations were measured in two groups of infants and in adult human volunteers. As expected, a diurnal rhythm was seen in adults. A diurnal rhythm was also found for cortisol and endorphin levels in neonates (3 to 4 days postnatally) with minimal stress and in infants who were clinically severely stressed. There was not a significant difference between the morning and afternoon concentrations of ACTH in these infants, but the afternoon concentrations were lower than the morning's, as would be expected. We found that a diurnal rhythm does exist in neonates within the first few days of postnatal life and that the continuous lighting and medical and nursing interventions do not interfere with this rhythm.
Source: PubMed Central
Authors: K W Hindmarsh, L Tan, K Sankaran, V A Laxdal
Language: English
Subfield: Behavioral Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
Funder: Medical Research Council
OpenAlex ID: W1489158449