Application of kinetic modeling to mineral metabolism management.

Patients with CKD face many consequences of renal failure, including disorders of bone and mineral metabolism. The current approach to management of these mineral metabolism issues lacks comprehensive quantitative assessment, so a kinetic modeling program has been designed to quantify intake and removal of phosphorus and calcium, as well as provide recommendations for treatment and prescriptions based on total mass balance and serum concentrations. This program is known as phosphorus kinetic modeling or PKM.

Sensitivity of NOS-dependent vascular relaxation pathway to mineralocorticoid receptor blockade in caveolin-1-deficient mice.

Endothelial caveolin-1 (cav-1) is an anchoring protein in plasma membrane caveolae where it binds endothelial nitric oxide synthase (eNOS) and limits its activation, particularly in animals fed a high salt (HS) diet. Cav-1 also interacts with steroid receptors such as the mineralocorticoid receptor (MR). To test the hypothesis that vascular reactivity is influenced by an interplay between MR and cav-1 during HS diet, we examined the effects of MR blockade on NOS-mediated vascular relaxation in normal and cav-1-deficient mice.

Increased vascular angiotensin type 2 receptor expression and NOS-mediated mechanisms of vascular relaxation in pregnant rats.

Normal pregnancy is associated with reduced blood pressure (BP) and decreased pressor response to vasoconstrictors, even though the renin-angiotensin system is upregulated. Angiotensin II (ANG II) activates both angiotensin type 1 receptors (AT(1)Rs) and angiotensin type 2 receptors (AT(2)Rs). Although the role of the AT(1)R in vascular contraction is well documented, the role of the AT(2)R in vascular relaxation, particularly during pregnancy, is less clear.

Trans-sodium crocetinate and hemorrhagic shock.

Trans-sodium crocetinate (TSC) has been found to alleviate the symptoms of hemorrhagic shock in that, after the drug is given to hemorrhaged rats, blood pressure rises, elevated lactate levels are reduced, cellular damage in the liver and kidney is less, and survival is increased. The mechanism of action proposed for TSC is that it increases the diffusion of oxygen through blood plasma and into the tissue. The study reported here explores another proposed mechanism, the scavenging of free radicals.

trans-Sodium crocetinate and diffusion enhancement.

trans-Sodium crocetinate (TSC) increases the diffusion coefficient of glucose through water by about 25-30%. This is the same percentage increase that TSC causes in the diffusivity of oxygen through water. TSC is also found to induce order in the surrounding water structure through increased hydrogen bonding of the water molecules, and molecular simulations suggest that the increase in diffusivity occurs only in these ordered regions.

Neurovascular mechanisms of hypertension in pregnancy.

Normal pregnancy is associated with significant changes in the neuronal and vascular control mechanisms of blood pressure (BP). Preeclampsia (PE) is a major complication of pregnancy characterized by proteinuria, and increased vascular resistance and BP. If untreated, PE leads to eclampsia with serious seizures and severe hypertension.

TSC for hemorrhagic shock: effects on cytokines and blood pressure.

Previous studies have shown that administering trans-sodium crocetinate (TSC) as a treatment of hemorrhagic shock leads to increased whole-body oxygen consumption and survival as well as protection of the liver and kidney. It has been suggested that TSC increases oxygen delivery by increasing the diffusivity of oxygen through plasma. However, as with any novel mechanism of action, there are always questions about whether the results could also be ascribed to other, previously described mechanisms of action.