Chronotropic response of spontaneously beating mouse atria to various concentrations of glucose.
The effect of different concentrations of glucose on the chronotropic activity of isolated mouse atrial preparations was studied. It was found that glucose in the concentrations from 2.2 X 10(-2)M to 8.8 X 10(-2)M was ineffective to change the chronotropic activity of isolated mouse atria. Moroever, the effects of bethanechol and norepinephrine on the chronotropic activity of isolated atria were not modified in the presence of 8.8 X 10(-2)M glucose. However, it was observed that the presence of high glucose did in fact reduce the contraction amplitude, and in the presence of 8.8 X 10(-2)M, glucose, the contraction amplitude was reduced to almost 50% of its initial contraction amplitude in the bathing medium containing 1.1 X 10(-2)M glucose. Possibility to explain such phenomenon is discussed.
Wong
K K
KK
Department of Pharmacology, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China.
D000818:Animals; D016275:Atrial Function; D018723:Bethanechol; D001626:Bethanechol Compounds / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology*; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009200:Myocardial Contraction / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D009997:Osmotic Pressure
D001626:Bethanechol Compounds; D018723:Bethanechol; D005947:Glucose; D002118:Calcium; D009638:Norepinephrine