Blum J J
Duke University Medical Center, Durham, North Carolina 27710, USA.
Biol Cell. 1996;87(1-2):9-16.
An acute decrease in osmolality causes a rapid change in the shape of the parasitic protozoan Leishmania donovani as determined by light microscopy and by flow cytometry. Incubation of the cells is an isotonic buffer supplemented with glucose. 2-deoxyglucose (2-DG), alanine, or proline also causes a shape change, presumably due to the swelling caused by the water that accompanies these substrates as they are actively transported into the cells. Hypo-osmolality also causes a rapid release of alanine and several other amino acids via a swelling activated amino acid channel. A sudden increase in osmolality causes a change in shape, an inhibition in the rates of oxidation of alanine, proline, leucine, and glucose, and in the rates of uptake of 2-aminoisobutyrate (AIB) and 2-DG. The protein kinase inhibitors staurosporine and genistein inhibited the rates of oxidation of alanine, glucose, and proline in a culture-age dependent manner and also altered the rate of release of AIB in response to hypo-osmotic stress. The possible roles of protein kinases in the culture-age dependent changes in the uptake, release and metabolism of several amino acids and of glucose are discussed.
通过光学显微镜和流式细胞术测定，渗透压的急剧降低会导致寄生原生动物杜氏利什曼原虫的形状迅速改变。细胞在补充有葡萄糖的等渗缓冲液中孵育。2-脱氧葡萄糖（2-DG）、丙氨酸或脯氨酸也会导致形状改变，推测是由于这些底物在被主动转运进入细胞时伴随的水引起的肿胀。低渗也会通过肿胀激活的氨基酸通道导致丙氨酸和其他几种氨基酸的快速释放。渗透压的突然升高会导致形状改变，抑制丙氨酸、脯氨酸、亮氨酸和葡萄糖的氧化速率，以及2-氨基异丁酸（AIB）和2-DG的摄取速率。蛋白激酶抑制剂星形孢菌素和染料木黄酮以培养年龄依赖性方式抑制丙氨酸、葡萄糖和脯氨酸的氧化速率，并且还改变了低渗应激下AIB的释放速率。讨论了蛋白激酶在几种氨基酸和葡萄糖的摄取、释放和代谢的培养年龄依赖性变化中的可能作用。
