Endotoxemia reduced HPV (∆PAP control: 121.2 ± 8.7% vs. LPS 19.5 ± 8.0%, means ± SEM) while inhibition of Kv3.4 with 50 nM BDS-I augmented HPV in endotoxemic but not in control lungs (∆PAP control BDS-I: 116.6 ± 16.0% vs. LPS BDS-I 84.4 ± 18.2%, means ± SEM). This evidence concerns the gene KCNC4 and serum lipopolysaccharide activity.