Peña James R, Wolska Beata M
Center for Cardiovascular Research, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
Basic Res Cardiol. 2005 Mar;100(2):147-53. doi: 10.1007/s00395-004-0503-6. Epub 2004 Nov 24.
We evaluated the effect of the inhalant anesthetic isoflurane and the injectable combination of anesthetics ketamine/inactin on cardiac function by measuring left ventricular (LV) pressure in situ during control conditions and during beta-adrenergic stimulation with isoproterenol (ISO). The control heart rate (HR) and the maximal rate of contraction were significantly higher in the isoflurane group, but there was no difference in the rate of relaxation. During the ISO (0.32 ng g body wt(-1) min(-1)) stimulation the developed pressure (DP) increased 9.8 +/- 1.8% (n = 11) in the ketamine/inactin group and was unchanged in the isoflurane group. The HR increased 28.4 +/- 4.8% (n = 11) in the ketamine/inactin group and only 3.4 +/- 0.6% (n = 11) in the isoflurane group. The rate of contraction increased 103.2 +/- 9.3% (n = 11) and 13.6 +/- 4.6% (n = 11) in the ketamine/inactin and isoflurane groups, respectively. At this dose of ISO the rate of relaxation did not change significantly. In control conditions there was no difference in levels of cAMP between the groups (2.29 +/- 0.25 pmol/mg protein (n = 5) in the ketamine/inactin group and 2.79 +/- 0.35 pmol/mg protein (n = 6) in the isoflurane group). However, during the ISO stimulation the cAMP level increased only in the ketamine/ inactin group of animals (3.50 +/- 0.30 pmol/mg protein; n = 5). This level was significantly higher than the level in the isoflurane group stimulated with ISO (2.22 +/- 0.30 pmol/mg protein; n = 6). In summary, our results indicate that the anesthetics differ significantly in the extent of depression of the basal and beta-adrenergic stimulated state with the second messenger cAMP playing a prominent role.
我们通过在对照条件下以及在用异丙肾上腺素（ISO）进行β-肾上腺素能刺激期间原位测量左心室（LV）压力，评估了吸入性麻醉剂异氟烷以及注射用麻醉剂氯胺酮/戊巴比妥钠组合对心脏功能的影响。异氟烷组的对照心率（HR）和最大收缩速率显著更高，但舒张速率没有差异。在ISO（0.32 ng g体重⁻¹ 分钟⁻¹）刺激期间，氯胺酮/戊巴比妥钠组的舒张期压力（DP）增加了9.8±1.8%（n = 11），而异氟烷组则没有变化。氯胺酮/戊巴比妥钠组的HR增加了28.4±4.8%（n = 11），而异氟烷组仅增加了3.4±0.6%（n = 11）。氯胺酮/戊巴比妥钠组和异氟烷组的收缩速率分别增加了103.2±9.3%（n = 11）和13.6±4.6%（n = 11）。在此剂量的ISO下，舒张速率没有显著变化。在对照条件下，各组之间的环磷酸腺苷（cAMP）水平没有差异（氯胺酮/戊巴比妥钠组为2.29±0.25 pmol/mg蛋白质（n = 5），异氟烷组为2.79±0.35 pmol/mg蛋白质（n = 6））。然而，在ISO刺激期间，只有氯胺酮/戊巴比妥钠组动物的cAMP水平升高（3.50±0.30 pmol/mg蛋白质；n = ）。该水平显著高于用ISO刺激后的异氟烷组（2.22±0.30 pmol/mg蛋白质；n = 6）。总之,我们 的结果表明，麻醉剂在基础状态和β-肾上腺素能刺激状态的抑制程度上存在显著差异，第二信使cAMP起着重要作用。
