Transepithelial Potential in Mesonephric Nephrons of 7-day-old Chick Embryos in Relation to the Histochemically Detected Sodium Pump

Title:

Transepithelial Potential in Mesonephric Nephrons of 7-day-old Chick Embryos in Relation to the Histochemically Detected Sodium Pump

Creator:

Zdeňka Zemanová and Ujec, E.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:1254c46e-2252-4e2b-babc-dbc8c9aa2b77
uuid:1254c46e-2252-4e2b-babc-dbc8c9aa2b77
issn:0862-8408

Subject:

Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Chick embryonic kidney, Tubular segments, Transepithelial potential difference, Ouabain-sensitive K+-NPPase, Active transport, 14, and 612

Type:

article, studie, model:article, and TEXT

Format:

print, bez média, and svazek

Description:

In order to obtain basic information on the transport properties of differentiating embryonic nephrons, we examined the 7-day-old chick mesonephros by measuring the transtubular epithelial potential difference (TPD) and by histochemical detection of Na,K-ATPase activity. TPD as an indicator of the electrogenic transport was measured in individual segments of superficial nephrons in vivo. Their electric polarity was always lumen-negative. TPD was reduced by addition of 10 mM KCN applied to the mesonephric nephrons from the outside. In the proximal tubules, TPD was significantly lower (mean±SD: -1.0±0.5 mV) than in the distal and collecting tubules (-2.2±1.0 mV, pŁ0.05). Activity of the sodium pump was evaluated histochemically by detection of ouabain-sensitive potassium-dependent p-nitrophenyl phosphatase in cryostat sections of the mesonephros. The enzyme activity was demonstrated only in distal tubules and in the collecting ducts, but not in the proximal tubules. These findings have revealed significant differences between embryonic nephron segments: the distal tubule, in contrast to the proximal one, is supplied by the sodium pump and is able to generate higher TPD. Therefore, we consider that it is only the distal nephron, which possesses the ability of active transport., Z. Zemanová, E. Ujec., and Obsahuje bibliografii

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2002 Volume:51 | Number:1

Harvested from:

CDK

Metadata only:

false