Q2. What is the role of clock genes in gastrointestinal motility?
Clock genes can change heir phase of expression in response to changes in he feeding cycle, indicating that feeding is an important ue for gastrointestinal clock gene expression.
Q3. What is the role of clock genes in the development of gastrointestinal ymptoms?
disruption of the lock mechanism such as occurs with shift work has been ssociated with the development of gastrointestinal ymptoms.
Q4. What is the role of clock genes in gastrointestinal organs?
Because gene array studies ave shown that approximately 8%–10% of all genes in eripheral organs such as the heart and the liver are nder circadian coordination, it is conceivable that a ubset of gastrointestinal genes are under clock gene ontrol as well.
Q5. How were clock genes expressed in the gastrointestinal tract?
To determine whether rhythmically expressed clock enes in the gastrointestinal tract were driven by the ight-dark cycle, mice were housed in constant darkness o eliminate the effect of light as a synchronizer of clock ene expression, with ad libitum access to food.
Q6. What is the role of the myenteric plexus in astrointestinal mot?
The myenteric plexus is an imortant site of neurotransmitter synthesis and integrates astrointestinal motility into recognizable patterns.
Q7. what is the role of lock genes in cell proliferation and otility?
The preominant expression of clock genes in the epithelial cells nd the myenteric plexus suggests a possible role for lock genes in the coordination of cell proliferation and otility.
Q8. How long did the mice have to be fed?
To examine whether feeding time can affect thehase of colonic clock gene expression, mice were fed for 8 hours or for 1 week during the day from 0800 until 200.
Q9. What is the mechanism of acrophase shift in the hepatic clock gene?
it has been shown that heatic clock genes shifted their acrophase while receiving otal parenteral nutrition during the light cycle, thus ompletely bypassing direct contact of food with the astrointestinal epithelium.
Q10. What is the mechanism by which timed feeding affects the acrophase of clock genes?
20 Although timed feeding has been associted with an increase in food-anticipatory behavior (inreased locomotor activity preceding a daily scheduled eal), food-anticipatory behavior by itself does not shift he phase of clock genes.
Q11. What is the mechanism of timed feeding in the liver?
It has recently been demnstrated that clock genes can shift their expression atterns in response to timed feeding in extraintestinal issues such as adipose tissue as well.
Q12. how long did acrophase for ad libium feeding occur?
The acrophase for PER2 as at 00:00 (95% CI: 22:16 – 01:40 in hh:mm) under ad ibitum feeding and at 11:56 (95% CI: 19:04 –23:08 in h:mm) following timed feeding.
Q13. What is the acrophase of ad libium mice?
3. Acrophase of distal colonic clock genes for mice with ad ibitum food access (solid squares) and following 48 hours of timed eeding (open squares).
Q14. What is the role of enes in gastrointestinal motility?
the authors speculate that a subset of enes that are important in gastrointestinal motility such s neurotransmitter enzymes and neurotransmitter reeptors are under direct or indirect clock control.
Q15. What is the acrophase of the clock genes in the stomach?
When aligning the rhythmically xpressed clock genes in order of their acrophase, cry1 nd Bmal1 peak before other clock genes, followed by er1-3 and cry2 (Figure 3; data shown for distal colon nly) in stomach, proximal, middle, and distal colon.