doi.org/10.1093/eurhea…
The rational= old forgotten concept (fig). AT II stimulates prox nephron Na/HCO3. Exact stoichiometry might differ but per Na retained +/- 3 HCO3 are retained. HCO3 levels can indicate neurohormonal activation. HCO3 levels can predict development of HF (pubmed.ncbi.nlm.nih.gov/25896890/ )