Figure 411

Voltage-dependent net magnesium (Mg) flux in the cortical thick ascending limb (cTAL). Within the isolated mouse cTAL, Mg flux (JMg) occurs in response to voltage-dependent mechanisms. With a relative lumen-positive transepithelial potential difference (Vt), Mg reabsorption increases (positive JMg). Mg reabsorption equals zero when no voltage-dependent difference exists, and Mg is capable of moving into the tubular lumen (negative JMg) when a lumen-negative voltage difference exists [1,16]. (From di Stefano and coworkers [16]).

Effect of hormones on magnesium (Mg) transport in the cortical thick ascending limb (cTAL). In the presence of arginine vasopressin (AVP), glucagon (GLU), human calcitonin (HCT), parathyroid hormone (PTH), 1,4,5-isoproteronol (ISO), and insulin (INS), increases occur in Mg reabsorption from isolated segments of mouse cTALs. These hormones have no effect on medullary TAL segments. As already has been shown in Figure 4-3, these hormones affect intracellular "second messengers" and cellular Mg movement. These hormone-induced alterations can affect the paracellular permeability of the intercellular tight junction. These changes may also affect the transepithelial voltage across the cTAL. Both of these forces favor net Mg reabsorption in the cTAL [1,2,7,8]. Asterisk—significant change from preceding period; JMg—Mg flux; C—control, absence of hormone. (Adapted from de Rouffignac and Quamme [1].)

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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