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Updated: Jul 16, 2026
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Quantitative Imaging of Lineage-specific Toll-like Receptor-mediated Signaling in Monocytes and Dendritic Cells from Small Samples of Human Blood
Published on: April 16, 2012
Beta receptor density in human lymphocyte membranes: changing with aging?
D W Gietzen1, T A Goodman, P G Weiler
1School of Medicine, University of California, Davis.
Journal of Gerontology
|July 1, 1991
Summary
Beta adrenergic binding sites (Bmax) increase with age in healthy individuals, contrary to some previous reports. This study found higher Bmax in aged subjects, suggesting age-related changes in receptor density are not universal.
Area of Science:
- Pharmacology
- Gerontology
- Immunology
Background:
- Beta adrenergic binding sites (Bmax) in human lymphocyte membranes show variable age-related changes in scientific literature.
- Previous studies report conflicting findings on whether Bmax increases, decreases, or remains unchanged with aging.
Purpose of the Study:
- To investigate the effect of aging on beta adrenergic binding sites (Bmax) in human lymphocytes.
- To clarify discrepancies in the literature regarding age-related changes in Bmax.
Main Methods:
- Utilized two specific beta receptor ligands to quantify Bmax in lymphocytes from young (19-39 years) and aged (51-90 years) healthy subjects.
- Excluded potential aged participants with high depression scores, as depression can affect Bmax.
Main Results:
- Bmax was significantly higher in the aged group compared to the young group in both studies (33% and 72.5% increase).
- No significant difference in antagonist affinity was observed between the young and aged groups.
Conclusions:
- Aging is associated with an increase in beta adrenergic binding sites (Bmax) in human lymphocytes in healthy individuals.
- Discrepancies in prior research may stem from variations in age ranges studied or the inclusion of depressed subjects.
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