Arteriovenous concentration differences

Table 8.12 Arteriovenous concentration differences in amino acids across the muscles in the leg of humans in the postabsorp-tive period...

It will be noticed from Table 4 that the lowest arteriovenous concentration differences are shown for 21-OH-pregnenolone, 16 -OH-DHA, and androstenediol (mainly 17a). It is possible that their low uptake by the placenta is due to their being diconjugated (Table 15), and it is possible that though the placenta can readily hydrolyze 3 8-sulfates it may have difficulty hydrolyzing (P6), and therefore removing from circulation, steroids sulfated at other positions. 

Ingestion of alcohol is traditionally considered a predisposing or precipitating factor in the gouty attack Studies performed in man by Lieber et al. (1962) have shown that the administration of ethanol provokes an increase in the serum concentration of uric acid, which was attributed to a decrease in its renal excretion More recently, ethanol infusion has been shown to enhance the production of uric acid by the liver, as measured from arteriovenous concentration differences during hepatic catheterisation in human volunteers (Grunst et al, 1973) ... 

From the differences in the arteriovenous concentration given in Table 4, it will be seen that for all the steroids listed there is a net production by the fetus and uptake by the placenta. The utilization by the placenta of certain of the steroids mentioned has been discussed in Sections 4.1 and... 

Arteriovenous concentration gradient Uptake of soluble anesthetics into highly perfused tissues may decrease gas tension in mixed venous blood. This can influence the rate of onset of anesthesia, since achievement of equilibrium is dependent on the difference in anesthetic tension between arterial and venous blood. 

Arginine, 2D biosynthesis, 435 catabolism, 431 134 chemical structure, 20 plasma concentration, 465 Argininosuccinate lyase, 439 Acgininosuccinate synthase, 439 Aromatic amino acids, chemical structure, 19 Arsenate, 840 Artenosclcrosis, 357 Arteriovenous differences, 19 199 Artery, physiology, 359 Ascoitale... 

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