Till sidans topp

Sidansvarig: Webbredaktion
Sidan uppdaterades: 2012-09-11 15:12

Tipsa en vän
Utskriftsversion

Hypersensitivity of Gi pr… - Göteborgs universitet Till startsida
Webbkarta
Till innehåll Läs mer om hur kakor används på gu.se

Hypersensitivity of Gi protein mediated muscarinic receptor adenylyl cyclase in chronic ischaemic heart failure in the rat.

Artikel i vetenskaplig tidskrift
Författare Michael Fu
Qing-Ping Feng
Qi-Ming Liang
Xiang-Ying Sun
Thomas Hedner
Johan Hoebeke
Åke Hjalmarson
Publicerad i Cardiovascular research
Volym 27
Nummer/häfte 11
Sidor 2065-70
ISSN 0008-6363
Publiceringsår 1993
Publicerad vid Wallenberglaboratoriet
Institutionen för invärtesmedicin, Avdelningen för klinisk farmakologi
Sidor 2065-70
Språk en
Länkar www.ncbi.nlm.nih.gov/entrez/query.f...
Ämnesord Adenylate Cyclase, metabolism, Animals, Carbachol, pharmacology, Cell Membrane, drug effects, Enzyme-Linked Immunosorbent Assay, Forskolin, pharmacology, GTP-Binding Proteins, metabolism, Guanylyl Imidodiphosphate, pharmacology, Immunoblotting, Male, Myocardial Ischemia, metabolism, Myocardium, cytology, metabolism, Rats, Rats, Sprague-Dawley, Receptors, Muscarinic, metabolism, Sarcolemma, metabolism
Ämneskategorier Cell- och molekylärbiologi

Sammanfattning

OBJECTIVE: The aim was to study the Gi protein mediated muscarinic signalling system in the myocardium of rats with chronic ischaemic heart failure. METHODS: Chronic ischaemic heart failure was induced by myocardial ischaemia (four weeks after coronary artery ligation) in rats. The densities and agonist affinities of muscarinic receptors, and the functional activity and concentration of Gi proteins were studied. RESULTS: In failing hearts, the activity of adenylyl cyclase stimulated by guanyliminodiphosphate (Gpp(NH)p) was decreased by 46%. Stimulated activities of adenylyl cyclase by both sodium fluoride and forskolin, however, remained unchanged. Carbachol depressed forskolin stimulated adenylyl cyclase more in membranes from failing hearts than those from normal hearts. The functional level of Gs protein as measured by a reconstitution assay in sarcolemmal membrane did not differ between the two groups. Furthermore, muscarinic receptors exhibited superhigh and low affinities for agonist in failing hearts whereas those in control hearts displayed only high and low affinities. No significant difference in the peptide equivalent amount of membrane bound Gi protein was found in either group. CONCLUSIONS: The experimental chronic failing heart due to myocardial ischaemia showed a depressed myocardial adenylyl cyclase signalling system. This may be due to the hypersensitivity of the Gi protein mediated muscarinic receptor-adenylyl cyclase system as shown by the increased inhibition of Gpp(NH)p mediated adenylyl cyclase, more potent inhibition of stimulated adenylyl cyclase by carbachol, and the superhigh affinity of the muscarinic receptors for carbachol.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11
Dela:

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?