Rapid synthesis and secretion of intestinal apolipoprotein A-IV after gastric fat loading in rats.
To further investigate the possible role of apolipoprotein A-IV (apo A-IV) in the short-term control of food intake, we examined the kinetics of intestinal apo A-IV synthesis and release into lymph and plasma after intragastric delivery of physiological amounts of lipid. Within 30 min of intragastric administration of 0.1 g of triglyceride, plasma and lymph levels of apo A-IV were similar to those produced by exogenous apo A-IV that inhibit food intake. Within 15 min, 5% of gastrically delivered radioactive lipid reached the distal small bowel and cecum; by 30 min radioactivity was evenly distributed throughout the small intestine, with 10-15% of the load in the distal gut. By 30 min, synthesis of apo A-IV was significantly stimulated in proximal and distal jejunum and distal ileum and remained elevated up to 4 h after the delivery of lipid. Our results indicate that the delivery of physiological amounts of lipid into the stomach produces a significant and rapid stimulation of apo A-IV secretion into lymph and plasma, together with a rapid delivery of lipid and increases in mucosal synthesis of apo A-IV along the entire length of the small intestine. The results support a possible role for apo A-IV in the short-term control of food intake and suggest a role for the entire gut in the integrative response of apo A-IV to a fat meal.
Rodriguez
M D
MD
Department of Physiology and Biophysics, Louisiana State University, Medical Center, Shreveport 71130, USA.
Kalogeris
T J
TJ
Wang
X L
XL
Wolf
R
R
Tso
P
P
D000818:Animals; D001054:Apolipoproteins A / Q000096:biosynthesis* / Q000378:metabolism; D002404:Catheterization; D004041:Dietary Fats; D004435:Eating / Q000502:physiology*; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage / Q000378:metabolism; D005753:Gastric Mucosa / Q000502:physiology*; D007700:Kinetics; D008196:Lymph / Q000502:physiology; D008208:Lymphatic System / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013270:Stomach / Q000502:physiology*; D013997:Time Factors; D014304:Triolein / Q000008:administration & dosage / Q000378:metabolism
D001054:Apolipoproteins A; D004041:Dietary Fats; D005217:Fat Emulsions, Intravenous; C022205:apolipoprotein A-IV; D014304:Triolein