期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：23
页码：7580-7584
DOI：10.1073/pnas.79.23.7580
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The internal dialysis technique has been applied to Limulus ventral photoreceptors. This method potentially allows quantitative control of the concentration of diffusible molecules within living cells. During dialysis, Limulus photoreceptors retained their ability to respond to light. Under conditions of dim illumination, responses were normal for close to an hour. In bright light, abnormalities developed more rapidly. The reversible effects of raising the dialysate Mg2+ concentration and the entrance of rhodamine-labeled albumin into cells shows that the dialysis method is useful for assaying the effects of small or large molecules on visual transduction. This method has been used to examine the effects of nucleotide triphosphates and cyclic nucleotides. The results show that nucleotide triphosphates (5-10 mM) are required to maintain a low rate of spontaneous quantum bumps. The importance of cyclic nucleotides in transduction is less clear; the light response was reduced by either cGMP or cAMP but only at very high concentrations (10 mM).
