Zarogiannis Sotirios, Vogiatzidis Konstantinos, Hatzoglou Chryssi, Liakopoulos Vassilios, Potamianos Spyros, Eleftheriadis Theodoros, Dovas Spyros, Kourti Panagiota, Gourgoulianis Konstantinos, Molyvdas Paschalis-Adam, Stefanidis Ioannis
Department of Nephrology, Medical School, University of Thessaly, Larissa, Greece.
Adv Perit Dial. 2007;23:34-7.
The peritoneal mesothelium is one of the main barriers to ion transport in peritoneal dialysis. In a previous study, we showed the existence of a micro-opioid influence on the in vitro ionic permeability of serosal membranes (specifically, pleura and pericardium), which become less permeable to ionic currents after the action of morphine. In the present study, we used Ussing chamber experiments to investigate the effect of morphine on the transmesothelial electrical resistance (RTM) of isolated parietal sheep peritoneum. Peritoneal samples from the diaphragm of adult sheep were isolated directly after the death of the animals and were transferred to the laboratory within 30 minutes in a cooled Krebs-Ringer bicarbonate solution (4 degrees C, pH 7.5) bubbled with 95% O2/5% CO2. A planar sheet of parietal peritoneum was mounted in an Ussing-type chamber and morphine (10(-9) mol/L) was added apically and basolaterally. The RTM was measured before and serially for 30 minutes after the addition of morphine. Because active ion transport is temperature dependent, the Ussing chamber was held at 37 degrees C. Results presented are the mean +/- standard error of 6 experiments. The control RTM (before the addition of morphine) was 20.26 +/- 0.57 Omega x cm2. Addition of morphine basolaterally induced, within 1 minute, an increase in RTM of 24% +/- 4.8%, which declined thereafter (p < 0.01). When morphine was added apically, the results were not similar, because no significant change occurred in the RTM. The RTM is an established surrogate of peritoneal permeability. The results of the present study indicate rapid action of basolaterally added morphine on the permeability of the parietal peritoneum. The observed increase in the RTM indicates the existence in the parietal peritoneum of micro-opioid receptors that seem to prevail basolaterally. The clinical implications of these results should be further investigated.
腹膜间皮是腹膜透析中离子转运的主要屏障之一。在先前的一项研究中,我们发现微量阿片类物质对浆膜(具体为胸膜和心包膜)的体外离子通透性有影响,吗啡作用后,浆膜对离子电流的通透性降低。在本研究中,我们使用尤斯灌流小室实验来研究吗啡对分离的绵羊壁层腹膜跨间皮电阻(RTM)的影响。成年绵羊死后立即直接从膈肌获取腹膜样本,并在30分钟内转移至实验室,置于用95% O2/5% CO2鼓泡的冷却的 Krebs-Ringer 碳酸氢盐溶液(4℃,pH 7.5)中。将一片壁层腹膜安装在尤斯型小室中,在顶端和基底外侧加入吗啡(10(-9) mol/L)。在加入吗啡之前及之后连续30分钟测量RTM。由于主动离子转运依赖温度,尤斯灌流小室保持在37℃。给出的结果是6次实验的平均值±标准误差。对照RTM(加入吗啡前)为20.26±0.57Ω×cm2。在基底外侧加入吗啡后1分钟内,RTM增加24%±4.8%,此后下降(p<0.01)。当在顶端加入吗啡时,结果不同,因为RTM没有显著变化。RTM是腹膜通透性的既定替代指标。本研究结果表明基底外侧加入的吗啡对壁层腹膜通透性有快速作用。观察到的RTM增加表明壁层腹膜中存在微量阿片类受体,且这些受体似乎在基底外侧占主导。这些结果的临床意义应进一步研究。