These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Effect of Cl-, Na+, and amiloride on the electrical properties of dog tracheal epithelium, in vitro. Author: Estep JA, Zorn JP, Marin MG. Journal: Am Rev Respir Dis; 1982 Oct; 126(4):681-5. PubMed ID: 7125361. Abstract: We investigated the effects on the cellular electrical properties of changes in the chemical gradient of Cl- and Na- across the luminal membrane of dog tracheal cells. We used standard microelectrode techniques to measure the electrical profile of these cells during Cl- and Na+ substitution in the luminal solution and during the addition of 10(-4) M amiloride, a Na+ conductance blocker, to the luminal solution. In 111 cell penetrations, we observed an apparent bimodal distribution of luminal membrane potential. About 75% of the cells constituted the lower mode, and the greatest number of penetrations in this mode had luminal potentials of -10 to -15 mV. The greatest number of penetrations in the higher mode had luminal potentials of -40 to -45 mV. In 16 penetrations, Cl- substitution changed the luminal membrane potential (+/- SE) by +12.3 +/- 0.6 mV and transepithelial potential by +11.6 +/- 0.9 mV. Both Na+ substitution and amiloride addition resulted in a minimal hyperpolarization of the luminal membrane potential with only a slight change in the submucosal potential. These results suggested the Cl- conductance contributed to a greater extent than that of Na+ to the maintenance of the luminal membrane potential difference and supported the model recently reviewed by Frizzell and coworkers (5) proposing Na+-dependent electrogenic CL- secretion in dog tracheal cells.[Abstract] [Full Text] [Related] [New Search]