Regulation of the Basolateral Na + , K + -ATPase in the Activation of Electrogenic Na + Absorption Induced by Isoproterenol in the Rat Distal Colon

[6]-Gingerol Induces Amiloride-Sensitive Sodium Absorption in the Rat Colon via the Capsaicin Receptor TRPV1 in Colonic Mucosa

[6]-Gingerol possesses various beneficial pharmacological and therapeutic properties, including anti-carcinogenic and anti-inflammatory properties and the ability to regulate intestinal contraction. Recently, our group observed that the serosal administration of [6]-gingerol stimulated electrogenic sodium absorption in the rat colon via the capsaicin receptor, TRPV1. TRPV1 is known to be expressed in both the mucosal epithelium and the muscle layers in the colon. In the present study, we assessed whether [6]-gingerol stimulated sodium absorption via TRPV1 in the colonic mucosal epithelium. We compared the effect of [6]-gingerol on TRPV1-dependent colonic sodium absorption in the colon preparation with or without muscle layer. All experiments were performed by measuring the transmural potential difference (ΔPD) in an Ussing chamber system. [6]-Gingerol induced positive ΔPD when administered to the serosal side of the colon, and this effect was significantly larger in the colon preparation without muscle layer than in that with the muscle layer. In the colon preparation without muscle layer, the [6]-gingerol-dependent induction of ΔPD was markedly suppressed by mucosal addition of amiloride, a selective inhibitor of epithelial sodium channel. ΔPD induction by [6]-gingerol was considerably diminished by capsazepine, an inhibitor of the capsaicin receptor TRPV1, but not by AP-18, an inhibitor of TRPA1. These results suggest that [6]-gingerol induces amiloride-sensitive electrogenic sodium absorption in the rat colon via TRPV1 expressed in the colonic mucosal epithelium, and that this effect is independent of TRPV1 in the colonic muscle layer.

Beneficial effects of fluid resuscitation via the rectum on hemodynamic disorders and multiple organ injuries in an experimental severe acute pancreatitis model

OBJECTIVES

Exaggerated hydration is harmful for patients with severe acute pancreatitis (SAP), and it can increase mortality rate. In this study, we investigated the role of fluid resuscitation via the rectum (FRVR) on the hemodynamic state and compared FRVR with intravenous fluid resuscitation (IVFR) on resuscitation effect and organ function in an early stage of SAP.

METHODS

We studied whether FRVR corrects hemodynamic disorders at an early stage of SAP in Spraque-Dawley (SD) rats and whether it mitigates organ dysfunction and whether FRVR is superior to IVFR.

RESULTS

In both IVFR and FRVR groups, we observed a rebound in the mean arterial pressure (MAP) after 5 h and 6 h of administration (p < 0.05), respectively. MAP of the FRVR group reached the same level as the SHAM group at the end of the treatment, with hematocrit declining compared with the non-fluid resuscitation (NFR) group (p < 0.05). A concomitant increase in abdominal ascites and the lung wet/dry ratio by IVFR was depressed in the FRVR group (p < 0.05). Liver function was ameliorated in both fluid resuscitation groups (p < 0.05), consistent with histopathological improvement. TNF-α in serum and MPO in the lungs and jejunum of the FRVR group were lower than the IVFR group (p < 0.05). Pancreas histopathological injuries were ameliorated by both IVFR and FRVR (p < 0.05).

CONCLUSIONS

Our findings suggested FRVR is a potential supplementary method for fluid management in an early stage of SAP and FRVR should be studied further.