In the context of sepsis, arterial underfilling arising from systemic inflammation-induced arterial vasodilation serves as a robust trigger for the activation of the sympathetic nervous system (SNS), the renin–angiotensin–aldosterone axis (RAAS), and the non-osmotic release of vasopressin (AVP) (Gomes et al., 2020). The gene discussed is REN; the disease is Sepsis.