This post is showing the sodium transport coupled with the transport of the lactate ion in the apical membrane of the S1 segment of the proximal tubule. Monocarboxylates like L-lactate, propionate, butyrate, or nicotinate can be cotransported with sodium
- The Na/K ATPase, which brings 2 potassium ions into the cell and releases 3 sodium ions into the interstitial space.
- The sodium/lactate cotransporter (SMCT2) at the apical membrane, which brings in 2 sodium ions from the filtrate together with 1 lactate ion.
This will be shown again in a future post when urate transport is reviewed. It will also be reviewed when SMCT1 is shown in the S3 segment of the proximal tubule
