Transcapillary PO Gradients in Contracting Muscle of Rat Model of Sepsis.

Introduction: This study aimed to evaluate the effect of cecal ligation and puncture (CLP)-induced sepsis on transcapillary PO gradients (ΔPO) in contracting skeletal muscles.

Methods: Male Wistar rats (n = 16, 10 weeks old) were randomly assigned to sham or CLP groups. Seven days after surgery, microvascular (POmv) and interstitial (POis) PO levels in the tibialis anterior muscle were measured using the phosphorescence quenching method during the transition from rest to electrically induced muscle contractions. ΔPO was calculated as POmv minus POis.

Results: At rest, there were no differences in POmv, POis, and ΔPO between the sham and CLP groups. The POmv and POis decreased during the transition from rest to contractions in both groups. During muscle contractions, the POmv and ΔPO were significantly lower in the CLP group than in the sham group (POmv, 7.79 ± 5.03 vs. 4.43 ± 2.23; ΔPO, 5.50 ± 4.46 vs. 1.82 ± 2.66 mm Hg; sham vs. CLP; p < 0.05). The ΔPO of the rats in the sham group remained unchanged; however, it markedly decreased during muscle contractions in the CLP group.

Conclusion: Sepsis reduced ΔPO in contracting skeletal muscles.