缺氧程度增加对离体心房功能和能量平衡的种属依赖性影响。

Species-dependent effects of increasing hypoxia on functions and energy balance in isolated atria.

Froldi G, Pandolfo L, De Biasi M, Chinellato A, Ragazzi E, Caparrotta L, Fassina G

Department of Pharmacology, University of Padova, Italy.

Comp Biochem Physiol Comp Physiol. 1993 May;105(1):21-7. doi: 10.1016/0300-9629(93)90168-4.

Abstract

The hypoxia-induced changes of contractile force, frequency and diastolic tension in isolated atria from guinea pig, rat and rabbit were studied together with tissue content of adenine nucleotides, creatine phosphate and lactic acid. 2. Increasing hypoxia induced a progressive reduction of contractility in guinea pig, rat and rabbit atria. Hypoxia also induced a progressive reduction of frequency in rat atria, whereas atrial rate decreased significantly only during drastic hypoxia in guinea pig and rabbit. In spontaneously beating atria, hypoxia increased diastolic tension only in rat. 3. After 30 min of drastic hypoxia, ATP decreased in guinea pig and rabbit but not in rat atria. Creatine phosphate decreased and lactic acid increased in all three species. 4. These data suggest that: (a) hypoxia-induced changes in atrial function and in metabolic content are species-dependent; (b) hypoxia-induced inhibition of atrial activity could represent protection aimed at saving energy.

摘要

研究了低氧诱导的豚鼠、大鼠和兔离体心房收缩力、频率和舒张张力的变化，以及腺嘌呤核苷酸、磷酸肌酸和乳酸的组织含量。2. 低氧程度增加导致豚鼠、大鼠和兔心房收缩力逐渐降低。低氧还导致大鼠心房频率逐渐降低，而豚鼠和兔仅在严重低氧时心房率才显著下降。在自主搏动的心房中，低氧仅使大鼠的舒张张力增加。3. 严重低氧30分钟后，豚鼠和兔心房中的ATP含量降低，但大鼠心房中未降低。所有三个物种的磷酸肌酸含量均降低，乳酸含量均增加。4. 这些数据表明：(a) 低氧诱导的心房功能和代谢含量变化具有物种依赖性；(b) 低氧诱导的心房活动抑制可能是一种旨在节省能量的保护机制。