Submitted on August 1, 2007
Accepted on April 1, 2008
Blood flow responses in celiac and superior mesenteric arteries in the initial phase of digestion
Nami Someya1, Masako Yamaoka Endo2, Yoshiyuki Fukuba2, and Naoyuki Hayashi3*
1 Graduate School of Human-Environment Studies, Kyushu University, Kasuga, Japan
2 Department of Exercise Science and Physiology, Prefectural University of Hiroshima, Hiroshima, Japan
3 Graduate School of Human-Environment Studies, Kyushu University, Kasuga, Japan; Institute of Health Science, Kyushu University, Kasuga, Japan
* To whom correspondence should be addressed. E-mail: naohayashi{at}ihs.kyushu-u.ac.jp.
Blood flow (BF) responses in the celiac artery (CA) and superior mesenteric artery (SMA) during and immediately after a meal are poorly understood. We characterized postprandial BF responses in these arteries in the initial phase of digestion. After a baseline measurement in the overnight fasting state, healthy subjects ingested solid food (300 kcal) and water ad libitum within 5 min (4.6 ± 0.2 min, mean ± SEM), and then rested for 60 min in the postprandial state. Mean blood velocities (MBV) in CA (n = 7) and SMA (n = 9), and mean arterial pressure (MAP) were measured throughout the procedure. MAP was divided by the MBV to yield the resistance index (RI). The MBV in CA and SMA started increasing within a minute after beginning the meal. The MBV in CA rapidly reached its peak increase (60 ± 8 % change from baseline) at 5 ± 1 min after the start of the meal, whereas the MBV in SMA gradually reached its peak increase (134 ± 14 %) at 41 ± 4 min after the start of the meal, reflecting a decrease in RI for both CA and SMA. These findings suggested an earlier increase in CA and SMA MBV, implying that the increase of BF in some parts of the small intestine precedes the arrival of chyme.
