Absorptive state

During the work on the book some of us were recipients of grants from the Committee of the Council of Higher Education, the Israel Academy of Sciences and Humanities. L.P. Yarin and A. Mosyak were also partially supported by the Center of Absorption (State of Israel) and the Israel Council for Higher Education. 

In the post-absorptive state with the subject at rest not less than 12 h after the last meal, protein catabolism has been completed. An RQ... 

Figure 1-11-2. Metabolic Profile of the Well-Fed (Absorptive) State...

In the weU-fed, absorptive state (insulin), accumulating acetyl CoA is shuttled into the cytoplasm for fatty acid synthesis. OAA is necessary for this transport, and acetyl CoA can stimulate its formation from pyruvate (see Chapter 15, Figure 1-15-1). 

The absorptive state continues for 2-4 hours after food intake. As a result of food digestion, the plasma levels of glucose, amino acids, and fats (triacylglycerols) temporarily increase. 

During the absorptive state, the heart and neural tissue mainly use glucose as an energy source, but they are unable to establish any substantial energy stores. Heart muscle cells are in a sense omnivorous, as they can also use other substances to produce energy (fatty... 

Glucose is the sole fuel for the brain, and this need is easily met in the absorptive state. 

Figure 5-5. Metabolic activities of major organs during a short-term fast. The importance of the liver in providing glucose to support the brain and other glucose-requiring organs in the post-absorptive state is illustrated. The body relies on available glycogen stores as a ready source for glucose as fuel. PPP, pentose phosphate pathway FA, fatty adds TAG, triacylglycerol.

The answer is D. This student is still in the fed or absorptive state within 1 hour of a meal, so elevated levels of many nutrients derived from food digestion would be observed in her blood. This would include all items in the list except glucagon. High nutrient levels in the blood evoke increased insulin secretion from the beta cells and suppression of glucagon secretion by the alpha cells of the islets of Langerhans. Therefore, blood levels of glucagon would be decreased relative to other nutritional states. 

Major metabolic pathways in liver in the absorptive state. [Note The numbers in circles, which appear both on the figure and in the text, indicate important pathways for carbohydrate, fat, or protein metabolism.]... 

Increased protein synthesis The body cannot store protein in the same way that it maintains glycogen or triacylglycerol reserves. However, a transient increase in the synthesis of hepatic proteins does occur in the absorptive state, resulting in replacement of ary proteins that may have been degraded during the previous postabsorptive period (see Figure 24.3, ) ... 

Increased glucose transport Glucose transport into adipocytes is very sensitive to the concentration of insulin in the blood. Circulating insulin levels are elevated in the absorptive state, resulting in an influx of glucose into adipocytes (Figure 24.5, O). 

Which one of the following is elevated in plasma during the absorptive period (compared with the post-absorptive state) ... 

Definition of absorptive state and compounds found in the plasma during this period... 

The absorptive state is the two- to four-hour period after ingestion of a normal meal. During this interval, transient increases in plasma glucose, amino acids, and triacylglycerols occur, the last primarily as components of chylomicrons synthesized by the intestinal mucosal cells. 

The amounts of absorbed molecules in H3PW12O40 tend to be integral multiples of the number of protons (3, 6,9, etc.), suggesting that these molecules form stable secondary structures throughout the bulk. Transitions between the different absorption states take place as a result of pressure changes (235). These transitions are closely related to the catalytic behavior for the dehydration of alcohol, as described below. 

BMR is the amount of energy expended while at rest in a neutrally temperate environment, in the post-absorptive state (expressed in kcal/day). BMR decreases with age and with the loss of lean body mass. Increasing muscle mass increases BMR. Illness, previously consumed food and beverages, environmental temperature and stress levels can affect overall energy expenditure as well as the BMR. BMR is accurately determined by gas analysis (direct or indirect calorimetry) an estimation can be found using the equation ... 

Chylomicrons are synthesized in the intestine and transport dietary triglycerides and cholesterol. While circulating, the core triglycerides in these particles are hydrolyzed by lipoprotein lipase, which results in the production of a cholesterol-enriched remnant particle. When synthesized and initially released by the intestine, chylomicrons contain essentially no apoE, but as they circulate and are processed to remnants, the particles acquire apoE from other lipoprotein classes. This results in a shift of the distribution of apoE in plasma to the triglyceride-rich remnants in the absorptive state (Blum, 1982). 

Acknowledgments This research was supported by the Israel Science Foundation administrated by the Israel Academy of Sciences and Humanities, the Fund for the Promotion of Research at the Technion, and the Minerva Foundation in Munich. B.T. and D.B.-Z. are grateful to the Ministry of Immigrant Absorption, State of Israel, for a Kamea scholarship. 

C. The fate of glucose in the fed (absorptive) state 1. The fate of glucose in the liver... 

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