Permeability of sodium-potassium pump

Value ~9E-09 cm/sec
Organism Guinea Pig Cavia porcellus
Reference Brading AF, Widdicombe JH. An estimate of sodium-potassium pump activity and the number of pump sites in the smooth muscle of the guinea-pig taenia coli, using (3H)ouabain. J Physiol. 1974 Apr238(2):235-49. Abstract article 6PubMed ID4840873
Method Animals killed, caecum dissected, put in Krebs solution and They were then blotted and weighed, and after washing with ouabain/42K solution counted in a gamma scintillation counter, to determine the uptake of potassium by the tissue.
Comments Abstract: "6. Indirect calculations of sodium movements suggest that the sodium permeability may be about 0.9x10^-8 cm sec^-1 and the pump may generate a current of 0.9x10^-7 A cm^-2. This crossing an Ohmic membrane resistance of 30-60 kOmega cm^2 would be equivalent to a potential difference of 3-5 mV." Value derived from Indirect calculations of sodium movements
Entered by Uri M
ID 103033