Functional and quantitative measures of receptor-coupled G proteins in human mononuclear leukocytes: No change with age

Liza Barki-Harrington, Yakov Nechamkin, Gabriel Schreiber, Sofia Avissar

Research output: Contribution to journalArticlepeer-review

11 Scopus citations

Abstract

Aging has been associated with alterations in signal transduction for a number of neurotransmitter receptors in human tissues. Heterotrimeric G proteins play a pivotal role in postreceptor information transduction, by coupling a variety of hormone and neurotransmitter receptors to several intracellular effector functions. Developmental and age-related changes in the abundance of specific Gα subunits have been shown in the human brain. In the present study, functional and quantitative measures of G proteins were conducted in human mononuclear leukocytes obtained from 19 healthy subjects of increasing age. Gs protein function, assessed through cholera toxin- sensitive β-adrenergic and dopaminergic agonists induced increases in 3H- Gpp(NH)p binding capacities to membranes of mononuclear leukocytes, and Gi protein function, assessed through pertussis toxin-sensitive muscarinic agonist induced increase in guanine nucleotide binding capacity, were found to be unaltered by increasing age. Immunobloting analyses with specific polyclonal antibodies against Gα(s), Gα(i), and Gα(q) subunit proteins in mononuclear leukocyte membranes obtained from the same subjects showed that the quantities of these proteins in mononuclear leukocytes were as well independent of age. Insofar as age-related alterations in cellular information transduction mechanisms in peripheral tissues are important from the etiological, diagnostic, and pharmacological aspects of age-related disorders, it is important to know that both the coupling of receptors to G proteins, the function of these proteins, and their abundance in human peripheral mononuclear leukocytes stays unaltered by the aging process.

Original languageEnglish
Pages (from-to)351-363
Number of pages13
JournalExperimental Gerontology
Volume31
Issue number3
DOIs
StatePublished - 1 Jan 1996

Keywords

  • G proteins
  • age
  • dopamine receptors
  • mononuclear leukocytes
  • muscarinic
  • β-adrenergic

Fingerprint

Dive into the research topics of 'Functional and quantitative measures of receptor-coupled G proteins in human mononuclear leukocytes: No change with age'. Together they form a unique fingerprint.

Cite this