Persechini P M, Bisaggio R C, Alves-Neto J L, Coutinho-Silva R
Laboratório de Imunobiofísica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brasil.
Braz J Med Biol Res. 1998 Jan;31(1):25-34. doi: 10.1590/s0100-879x1998000100004.
The effects of extracellular nucleosides and nucleotides on many organs and systems have been recognized for almost 50 years. The effects of extracellular ATP (ATPo), UTPo, ADPo, and other agonists are mediated by P2 purinoceptors. One of the most dramatic effects of ATPo is the permeabilization of plasma membranes to low molecular mass solutes of up to 900 Da. This effect is evident in several cells of the lymphohematopoietic system and is supposed to be mediated by P2Z, an ATP(4-)-activated purinoceptor. Here, we review some basic information concerning P2 purinoceptors and focus our attention on P2Z-associated phenomena displayed by macrophages. Using fluorescent dye uptake, measurement of free intracellular Ca2+ concentration and electrophysiological recordings, we elucidate some of the events that follow the application of ATP to the extracellular surface of macrophages. We propose a regulatory mechanism for the P2Z-associated permeabilization pore. The presence of P2 purinoceptors in cells of the lymphohematopoietic system makes them potential candidates to mediate immunoregulatory events.
细胞外核苷和核苷酸对许多器官和系统的影响已被认识近50年。细胞外ATP（ATPo）、UTPo、ADPo及其他激动剂的作用是由P2嘌呤受体介导的。ATPo最显著的作用之一是使质膜对分子量高达900Da的低分子质量溶质具有通透性。这种作用在淋巴造血系统的几种细胞中很明显，并且被认为是由P2Z介导的，P2Z是一种由ATP（4-）激活的嘌呤受体。在此，我们综述一些有关P2嘌呤受体的基本信息，并将注意力集中在巨噬细胞所表现出的与P2Z相关的现象上。通过荧光染料摄取、细胞内游离Ca2+浓度的测量和电生理记录，我们阐明了将ATP应用于巨噬细胞细胞外表面后发生的一些事件。我们提出了一种与P2Z相关的通透孔的调节机制。淋巴造血系统细胞中P2嘌呤受体的存在使其成为介导免疫调节事件的潜在候选者。
