[Influence of ADP-ribose, AMP and adenosine on bioelectric activity of hibernating ground squirrel atrium and papillary muscle].
The aim of work was to investigate effects of adenosine, AMP and ADP-ribose (1x10(-5)) on bioelectric activity of atrium and papillary muscle of nonhibernating (rat) and hibernating (Yakutian ground squirrel) animals. Action potential (AP) was registered with use of standard microelectrode technique. AP duration (APD) at level of 90% repolarisation in rat atrium in control experiments was 30+/-5 ms, APD at level of 50% repolarisation was 12+/-2 ms. APD at level of 90% repolarisation in rat papillary muscle was 56+/-7 ms, at level of 50% repolarisation was 18+/-2 ms. APD at level of 90% repolarisation in ground squirrel atrium was 77+/-6, APD at level of 50% repolarisation was 38+/-6 ms. APD at level of 90% repolarisation in ground squirrel papillary muscle was 105+/-9 ms, APD at level of 50% repolarisation was 42+/-8 ms. Purine nucleotides and nucleoside, that were tested in work, except ADP-ribose, act as inhibitory factors and decrease APD both in rat and hibernating ground squirrel heart. ADP-ribose decreases APD in papillary muscle of hibernator but did not in its atrium. In ground squirrel atrium AMP and adenosine decrease APD at level of 50% repolarisation by 10+/-3% and 18+/-3% respectively. AMP and adenosine decrease APD at level of 90% repolarisation by 9+/-2% and 11+/-2% respectively. In ground squirrel papillary muscle ADP-ribose, AMP and adenosine decrease APD at level of 50% repolarisation by 26+/-8%, 23+/-8% and 26+/-7%. ADP-ribose, AMP and adenosine decrease APD at level of 90% repolarisation by 12+/-3%, 10+/-3%, 13+/-3%. Thus, decrease of APD in ground squirrel papillary muscle at level of 90% repolarisation during nucleotides and adenosine action was 2-2.5 fold less, than the rat.
Kuz'min
V S
VS
Abramochkin
D V
DV
Sukhova
G S
GS
Rozenshtraukh
L V
LV
D000200:Action Potentials; D000241:Adenosine / Q000378:metabolism / Q000494:pharmacology; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000249:Adenosine Monophosphate / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000378:metabolism; D016275:Atrial Function / Q000502:physiology*; D006325:Heart Atria / Q000187:drug effects / Q000378:metabolism*; D006605:Hibernation / Q000502:physiology*; D010210:Papillary Muscles / Q000187:drug effects / Q000502:physiology*; D011685:Purine Nucleotides / Q000378:metabolism; D051381:Rats; D011983:Receptors, Purinergic / Q000502:physiology; D012589:Sciuridae / Q000502:physiology*
D011685:Purine Nucleotides; D011983:Receptors, Purinergic; D000246:Adenosine Diphosphate Ribose; D000249:Adenosine Monophosphate; D000241:Adenosine