Metabolic interrelationships metabolism

Figure 20-7. Summary of the interrelationships in metabolism of amino sugars. (At asterisk Analogous to UDPGIc.) Other purine or pyrimidine nucleotides may be similarly linked to sugars or amino sugars. Examples are thymidine diphosphate (TDP)-glucosamine and TDP-N-acetylglucosamine.

Figure 27-1. Metabolic interrelationships between adipose tissue, the liver, and extrahepatic tissues. In extrahepatic tissues such as heart, metabolic fuels are oxidized in the following order of preference (1) ketone bodies, (2) fatty acids, (3) glucose. (LPL, lipoprotein lipase FFA, free fatty acids VLDL, very low density lipoproteins.)...

R. S. Flueck, J. A. "The Interrelationships Between Vitamin D and Parathyroid Hormone in Disorders of Mineral Metabolism in Man" (Proceedings of 2nd Vitamin D Symposium), Weisbaden, West Germany, Oct., 1974, In Press. 

In intact cell systems or vivo, the primary products of a-hydroxylation, 22. have not been detected. The principal urinary metabolites of NNN resulting from a-hydroxylation are keto acid 21 from 2 -hydroxyl at ion and hydroxy acid 21 from 5 -hydroxylation. Trace amounts of 7 y 21> H ve also been detected as urinary metabolites (34). The interrelationships of these metabolites as shown in Figure 2 have been confirmed by administration of each metabolite to F-344 rats (37). The other metabolites which are routinely observed in the urine are NNN-1-N-oxide U1 and 5-(3-pyridyl)-2-pyrrolidinone [norcotinine, ]. The p-hydroxy derivatives 2. 1 were also detected in the urine of NNN treated rats, but at less than 0.1% of the dose (36). An HPLC trace of the urinary metabolites of NNN is shown in Figure 3. Urine is the major route of excretion (80-90% of the dose) of NNN and its metabolites in the F-344 rat in contrast to NPYR which appears primarily as CO2 (70%) after a dose of 16 mg/kg (17). This is because the major urinary metabolite of NNN, hydroxy acid 21> fs not metabolized further, in contrast to 4-hy-droxybutyric acid [2, Figure 1] which is converted to CO2. In addition, a significant portion of NNN is excreted as NNN-l-N-oxide U ], a pathway not open to NPYR. 

Saz, H.J. and Lescure, O.L. (1966) Interrelationships between the carbohydrate and lipid metabolism of Ascaris lumbricoides egg and adult stages. Comparative Biochemistry and Physiology 18, 845-857. 

Although it ia becoming increasingly evident with each new discovery that the metabolism of no single foodstuff proceeds in a course entirely isolated from that of the other foodstuffs, the interrelationships are nowhere so apparent as they are between the utilization of carbohydrate and that of fat. The conversion of carbohydrate to fat is a phenomenon which has been repeatedly demonstrated experimentally the reverse change, namely, the conversion of natural fats to carbohydrate, is a disputed reaction and must certainly not occur except to a limited extent, if at all. 

Finally, the chemistry of the organism must be taken into account. Interrelationships among metals can rarely be explained on a purely chemical basis (i.e. inhibition of the uptake of the metal of interest and uptake of the competing metal). Even metals exhibiting the expected chemical antagonisms, may also initiate a cellular feedback, alter the overall biological metabolism or modify membrane permeability or the cells capacity to deal with the metal of interest. 

All life is unified by commonality of the molecules of life, cells, energy interrelationships, and metabolism... 

There are, however, more intricate interrelationships between the mycelial architecture of the filamentous organism and the productivity of these organisms. We have observed, for example, that bikaverin is deposited only at the branching points within the hyphae of G fujikuroi (Fig. 3). Below, we shall show that there are correlations between the global translational regulators responsible for both morphogenesis and secondary metabolism. 

Figure 5-4. Metabolic activities of major organs in the fed state. The relative activities of major metabolic pathways or processes in each of the organs are indicated by their font sizes. The exchange of nutrient materials and fuel molecules through the bloodstream illustrates the interrelationships of these organs. In the absorptive condition, all organs share the bounty of nutrients made available by digestion of food by the intestine. PPP, pentose phosphate pathway FA, fatty acids TAG, triacyl-glycerol.

Figure 6.1 The interrelationships between the disposition and toxicity of a foreign compound. The parent compound may undergo distribution out of the blood (d) to other tissues, and there cause toxicity by reaction with receptors (r). Alternatively, metabolism (m) may also occur and give rise to toxic metabolites (a), which react with critical targets (r). Metabolites may also distribute back into the blood (b) and be excreted (e).

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