Autoantibodies against M2 muscarinic receptors in patients with cardiomyopathy display non-desensitized agonist-like effects.

• Circulating autoantibodies against the human M2 muscarinic receptors have been previously shown in 38% of patients with idiopathic dilated cardiomyopathy. The functional properties of these autoantibodies are reported herein. They were able to decrease the cell beating frequency of myocytes in cultured neonatal rat heart cells in a dose-dependent manner without desensitization over a period of more than 5 hours whereas the non-specific muscarinic receptor agonist carbachol also inhibited the heart cell beating frequency but was desensitized within 1 hour. In the same cell culture, anti-M2 muscarinic receptor autoantibodies were not able to induce internalization of muscarinic receptor whereas carbachol did. These results demonstrate for the first time that anti-M2 muscarinic receptor autoantibodies from patients with idiopathic dilated cardiomyopathy have stimulatory muscarinic activity in vitro, which differ from normal muscarinic agonists by non-desensitization.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Cell- och molekylärbiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Cell and Molecular Biology (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Mikrobiologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Microbiology in the medical area (hsv//eng)

Nyckelord

Animals

Atropine

pharmacology

Autoantibodies

blood

isolation & purification

pharmacology

physiology

Binding Sites

drug effects

Carbachol

metabolism

pharmacology

Cardiomyopathy

Dilated

blood

immunology

physiopathology

Cells

Cultured

Depression

Chemical

Dose-Response Relationship

Drug

Down-Regulation

drug effects

Heart Rate

drug effects

Humans

Muscarinic Agonists

pharmacology

Muscarinic Antagonists

pharmacology

Myocardium

cytology

N-Methylscopolamine

metabolism

Rats

Rats

Wistar

Receptor

Muscarinic M2

Receptors

Muscarinic

immunology

metabolism

Time Factors

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)