Schwartz J H, Bethencourt D, Rosen S
Am J Physiol. 1982 Jun;242(6):F627-33. doi: 10.1152/ajprenal.1982.242.6.F627.
The mucosal surface of the turtle bladder consists of two major cell types, carbonic anhydrase-rich (CA) and granular (G) cells. These cells types may have specific transport functions. To separate and study these cells, they were removed from the bladder by collagenase digestion and then separated into two distant subpopulations by Ficoll discontinuous density-gradient centrifugation. By morphological criteria the lighter subpopulation (band II) consists primarily of CA cells and the denser population (band III) G cells. The distribution of two enzymes important for H+ transport, CA and glucose-6-phosphate dehydrogenase (G-6-PD), and the effect of specific transport inhibitors, acetazolamide and ouabain, on O2 consumption of these cells was examined. The CA activity of band II cells was 4.5 times greater than that of band III cells. The G-6-PD activity of band II cells was 2.2 times greater than that of band III cells. The rate of O2 consumption of band II cells, 4.73 microliters.mg protein-1.h-1, was reduced 40% by 5 X 10(-5) M acetazolamide but not by ouabain. Band III O2 consumption, 3.43 microliters.mg protein-1.h-1, was reduced 30% by 10(-4) M ouabain but not by acetazolamide. On the basis of the distribution of CA and G-6-PD and the effect of acetazolamide and ouabain on O2 consumption, we propose that CA cells are primarily responsible for H+ transport and G cells for Na+ transport.
龟膀胱的黏膜表面由两种主要细胞类型组成，即富含碳酸酐酶（CA）的细胞和颗粒（G）细胞。这些细胞类型可能具有特定的转运功能。为了分离和研究这些细胞，通过胶原酶消化将它们从膀胱中取出，然后通过菲可连续密度梯度离心法将其分离为两个不同的亚群。根据形态学标准，较轻的亚群（带II）主要由CA细胞组成，而密度较大的群体（带III）由G细胞组成。研究了对H⁺转运重要的两种酶，即CA和葡萄糖-6-磷酸脱氢酶（G-6-PD）的分布，以及特定转运抑制剂乙酰唑胺和哇巴因对这些细胞耗氧量的影响。带II细胞的CA活性比带III细胞高4.5倍。带II细胞的G-6-PD活性比带III细胞高2.2倍。带II细胞的耗氧率为4.73微升·毫克蛋白⁻¹·小时⁻¹，5×10⁻⁵M的乙酰唑胺使其降低了40%，但哇巴因没有使其降低。带III细胞的耗氧率为3.43微升·毫克蛋白⁻¹·小时⁻¹，10⁻⁴M的哇巴因使其降低了30%，但乙酰唑胺没有使其降低。根据CA和G-6-PD的分布以及乙酰唑胺和哇巴因对耗氧量的影响，我们提出CA细胞主要负责H⁺转运，而G细胞负责Na⁺转运。
