Zimmermann U, Hüsken D
Institut für Biophysikalische Chemie (ICH/2) der Kernforschungsanlage Jülich, Postfach 1913, D-5170 Jülich West Germany.
Plant Physiol. 1979 Jul;64(1):18-24. doi: 10.1104/pp.64.1.18.
The volumetric elastic modulus of the cell wall and the hydraulic conductivity of the cell membranes were measured on ligatured compartments of different sizes of Chara corallina internodes using the pressure probe technique. The ratio between intact cell surface area and the area of puncture in the cell wall and membrane introduced by the microcapillary of the pressure probe was varied over a large range by inserting microcapillaries of widely varying diameters in different sized compartments. The relationship of the elastic modulus and the hydraulic conductivity to turgor pressure was independent of the ratio of intact cell surface area to the area of injury. The increase in the hydraulic conductivity below 2 bar turgor pressure and the volume dependence of the elastic modulus were shown to be the same as those observed in intact nonligatured cells. Theoretical considerations of the possible influence of injury of the cell wall and cell membrane around the inserted microcapillary on the measurement of the water transport and cell wall parameters do not explain the experimental findings. Thus, mechanical artifacts, if at all present, are too small to account for the observed dependence of the hydraulic conductivity and the elastic modulus on turgor pressure. The pressure probe technique thus represents an accurate method for measuring water transport parameters in both giant algal cells and in tissue cells of higher plants.
采用压力探针技术，对不同大小的轮藻节间的结扎区进行测量，以测定细胞壁的体积弹性模量和细胞膜的水力传导率。通过在不同大小的区域插入直径差异很大的微毛细管，压力探针微毛细管在细胞壁和细胞膜上造成的完整细胞表面积与穿刺面积之比在很大范围内变化。弹性模量和水力传导率与膨压的关系与完整细胞表面积与损伤面积之比无关。低于2巴膨压时水力传导率的增加以及弹性模量的体积依赖性与在完整的未结扎细胞中观察到的情况相同。关于插入的微毛细管周围的细胞壁和细胞膜损伤对水运输和细胞壁参数测量可能产生的影响的理论思考无法解释实验结果。因此，即使存在机械假象，其影响也太小，无法解释观察到的水力传导率和弹性模量对膨压的依赖性。因此，压力探针技术是测量大型藻类细胞和高等植物组织细胞中水运输参数的一种准确方法。
