Effects of certain steroids on bioelectric current of isolated frog skin

1961 ◽  
Vol 200 (4) ◽  
pp. 797-800 ◽  
Author(s):  
Robert D. McAfee ◽  
William Locke

2-methyl-9 α-fluorohydrocortisone and hydrocortisone sodium succinate increase both the rate and duration and, therefore, total quantity of ion transported in the isolated short-circuited frog skin measured over a 24-hour period. The ion transport is directly related to the bioelectric current generated, and based on Ussing's work, is assumed identical to the net flux of sodium ion. These steroids may make available transport energy that is not available to the untreated half of the skin by rerouting enzymatic pathways or by lowering the resistance of the membrane to ion transport and thereby more efficiently utilizing the energy available for transport.

2018 ◽  
Vol 10 (44) ◽  
pp. 38006-38014 ◽  
Author(s):  
Xun Zhao ◽  
Ming Luo ◽  
Wenxia Zhao ◽  
Ruimei Xu ◽  
Yong Liu ◽  
...  

Author(s):  
Xu Xie ◽  
Zhoulan Yin ◽  
You Li ◽  
Ruixuan Tu ◽  
Yang Liu ◽  
...  

Metal-selenides are one of the next generation anode materials for sodium ion batteries (SIBs), but suffer from sluggish charge/ion transport, huge volume expansion and aggregation of particles. Herein, ZnSe/C composites...


2019 ◽  
Vol 286 (1896) ◽  
pp. 20182444 ◽  
Author(s):  
Isabelle Taubner ◽  
Marian Y. Hu ◽  
Anton Eisenhauer ◽  
Markus Bleich

Light has been demonstrated to enhance calcification rates in hermatypic coral species. To date, it remains unresolved whether calcifying epithelia change their ion transport activity during illumination, and whether such a process is mediated by the endosymbiotic algae or can be controlled by the coral host itself. Using a modified Ussing chamber in combination with H + sensitive microelectrode measurements, the present work demonstrates that light triggers the generation of a skeleton positive potential of up to 0.9 mV in the hermatypic coral Stylophora pistillata . This potential is generated by a net flux of cations towards the skeleton and reaches its maximum at blue (450 nm) light. The effects of pharmacological inhibitors targeting photosynthesis 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and anion transport 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) were investigated by pH microelectrode measurements in coral tissues demonstrating a rapid decrease in tissue pH under illumination. However, these inhibitors showed no effect on the electrophysiological light response of the coral host. By contrast, metabolic inhibition by cyanide and deoxyglucose reversibly inhibited the light-induced cation flux towards the skeleton. These results suggest that ion transport across coral epithelia is directly triggered by blue light, independent of photosynthetic activity of algal endosymbionts. Measurements of this very specific and quantifiable physiological response can provide parameters to identify photoreception mechanisms and will help to broaden our understanding of the mechanistic link between light stimulation and epithelial ion transport, potentially relevant for calcification in hermatypic corals.


FEBS Letters ◽  
1968 ◽  
Vol 2 (1) ◽  
pp. 4-6 ◽  
Author(s):  
Karl-Anders Karlsson ◽  
Bo E. Samuelsson ◽  
Göran O. Steen

Sign in / Sign up

Export Citation Format

Share Document