Adenosine Receptor by Adenine Nucleotides
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چکیده
Adenosine and adenine nucleotides shorten the action potential duration of atrial myocytes and activate a specific acetylcholine and adenosine receptor-operated potassium outward current referred to as IKACh,Ado The objective of this study was to determine whether adenine nucleotides shorten the action potential duration and increase IKAChAdo in guinea pig atrial myocytes by directly activating adenosine receptors. The potency and efficacy of AMP and adenosine in increasing KACh,Ado and shortening atrial action potential duration were similar; the EC50 values for AMP and adenosine were 3.4±0.8 and 3.1±0.4 ,M, respectively. Likewise, the maximum increases in IKACh,Ado caused byAMP and adenosine were similar (122±11% versus 123 ±9%). In comparison, ATP and the stable analogue of AMP, adenosine monophosphorothioate (AMPS),
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تاریخ انتشار 2005