Beta-Adrenergic and Muscarinic Receptor mRNA Accumulation in the Sinoatrial Node Area of Adult and Senescent Rat Hearts

Details

• Personal Author:
  Bourgeois F ; Dakhli T ; Elalouf JM ; Fellmann D ; Hardouin S ; Moalic JM ; Oubenaissa A ; Swynghedauw B ; Toraasson M
• Description:
  The sinoatrial (SA) node is the cardiac pacemaker and changes in its adrenergic-muscarinic phenotype have been postulated as a determinant of age-associated modifications in heart rate variability. To address this question, right atria were microdissected, the SA node area was identified by acetylcholinesterase staining, and, using a RT-PCR method, the accumulation of mRNA molecules encoding beta1- and beta2-adrenergic (beta1- and beta2-AR) and muscarinic (M2-R) receptor was quantified to define the proportion between beta-AR and M2-R mRNAs within the sinoatrial area of adult (3 months) and senescent (24 months) individual rat hearts. In adult hearts, the highest M2-R/beta-AR mRNA ratio was observed within the sinoatrial area compared with adjacent atrial myocardium, while in the senescent hearts, no difference was observed between sinoatrial and adjacent areas. This change was specific of the sinoatrial area since adult and senescent whole atrial or ventricular myocardium did not differ in their M2-R/beta-AR mRNA ratio, and was associated with a fragmentation of acetylcholinesterase staining of the senescent SA node. Quantitative changes in the expression of genes encoding proteins involved in heart rate regulation specifically affect the sinoatrial area of the senescent heart. [Description provided by NIOSH]
• Subjects:
  Animals Cardiovascular Diseases Cardiovascular System Genetics Laboratories Occupational Health Safety
• Keywords:
  Animal-studies Cardiovascular-disease Cardiovascular-function Cardiovascular-system Cardiovascular-system-disease Genes Heart Heart-rate Laboratory-animals Quantitative-analysis
• ISSN:
  0047-6374
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DBBS - Division of Biomedical and Behavioral Sciences
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  277-297
• Volume:
  100
• Issue:
  3
• NIOSHTIC Number:
  nn:20027956
• Citation:
  Mech Ageing Dev 1998 Feb; 100(3):277-297
• Federal Fiscal Year:
  1998
• Peer Reviewed:
  True
• Source Full Name:
  Mechanisms of Ageing and Development
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:c893d8c3384a9f46dbe7c9b2d8c8d6204cd415e026c561ab8d5f7a776719419593dc364e1cf1ee8ce1154067dcfa4ce4592cf398c492c62eca36fb147a3636cf
• Download URL:
  https://stacks.cdc.gov/view/cdc/189692/cdc_189692_DS1.pdf
• File Type:
  [PDF - 666.22 KB ]