TACR1 and Sepsis: Interestingly, disrupting the SP-NK1R axis through either the genetic deletion of the Tac1 gene, the pharmacological blockade of NK1R using L703606, or the combination of these two approaches had no significant effects on the expressions of NK1R in the liver (p > 0.05) and lungs (p > 0.05) in mice following CLP-surgery-induced sepsis.