Role of protein kinase G on the post-shock mesenteric lymph blockage ameliorating vascular calcium sensitivity

Abstract

PURPOSE:To investigate the role of protein kinase G (PKG) in blocking post-shock mesenteric lymph (PSML) return ameliorating the calcium sensitivity in hemorrhagic shock rats. METHODS:Male Wistar rats were randomly divided into sham, shock, shock+ligation (shock plus mesenteric lymph duct ligation (MLDL)), shock+drainage (shock plus PSML drainage) groups. After shock (hypotension 40mmHg) for three hours or corresponding times, the superior mesenteric artery (SMA) was taken out for detecting the PKG and phospho PKG (p-PKG) contents, and the vascular rings of SMA were prepared for assaying the calcium sensitivity using an isolated organ perfusion system. RESULTS:The PKG and p-PKG contents of SMA in shock group were significantly increased than that of sham group, and MLDL or PSML drainage reducing the levels of PKG and p-PKG. Meanwhile, the vascular calcium sensitivity in shock group was significantly lower than that of sham group, MLDL or PSML drainage enhanced the calcium sensitivity. After incubating with PKG regulators in shock+ligation and shock+drainage groups, the PKG agonist 8Br-cGMP reduced the contractility of vascular rings to gradient calcium ions and Emax and the PKG inhibitor agonist KT5823 elevated the calcium sensitivity significantly. CONCLUSION:Protein kinase G plays an important role in post-shock mesenteric lymph blockage improving vascular calcium sensitivity.

Mesenteric Lymph Drainage Alleviates Acute Kidney Injury Induced by Hemorrhagic Shock without Resuscitation

“…Afterward, the rats were subjected to abdominal dissection to separate the mesenteric lymph duct from the surrounding connective tissues to induce mesenteric lymph drainage. After a stabilization period of 30 min, the hemorrhagic shock model (40 mmHg, 3 h) was established in shock and drainage groups; mesenteric lymph drainage was performed from 1 h to 3 h of hypotension in the drainage group as previously described [10, 12]. At the same time, the rats in the sham group were anesthetized and received femoral and abdominal surgery as well as shock and drainage groups but did not undergo hemorrhage.…”

Estrogen Enhances the Microvascular Reactivity Through RhoA-ROCK Pathway in Female Mice During Hemorrhagic Shock

“…First, we only employed female mice to observe the roles of RhoA-ROCK pathway in mediating E2 favorable effect on vascular reactivity during hemorrhagic shock. Our previous studies have demonstrated in male animals that hemorrhagic shock resulted in a decreased vascular reactivity and the signal molecules of RhoA, MLCK, and PKG are involved in this process (20,32,33). Whether E2 plays a similar protective effect on vascular reactivity in males during hemorrhagic shock needs further investigation.…”