Gastrin metabolism in neonatal pigs and grower-pigs.
1. Half-life (1.7 +/- 0.1 min), distribution volume (146 +/- 12 ml/kg) and metabolic clearance rate (28 +/- 1 ml/kg/min) of little gastrin (G17) in neonatal pigs (N = 6; 3-12 days old) were significantly different from those in grower-pigs (N = 4; 161-170 days old) (2.4 +/- 0.1 min; 58 +/- 2 ml/kg; 7.9 +/- 0.3 ml/kg/min, respectively). 2. Half-life (33 +/- 4 min) and distribution volume (265 +/- 33 ml/kg) of big gastrin (G34) in neonatal pigs were greater but not significantly different from those in grower-pigs (24 +/- 2 min; 217 +/- 20 ml/kg, respectively). 3. Half-life of G17 in liver extracts from pigs 2-90 days old (40.4 +/- 4.2 min) was significantly longer than in kidney extracts (22.0 +/- 1.7 min). Half-lives of G34 in liver and kidney extracts from pigs 10-90 days old (78 +/- 6; 74 +/- 4 min, respectively) were significantly shorter than the corresponding values for 2-day-old pigs (134 +/- 3; 149 +/- 9 min, respectively). 4. Since G34 is the major circulating form of gastrin in neonatal pigs the relative longer half-life of G34 to G17 in these animals may contribute to the higher circulating gastrin concentration compared with that in older animals.
School of Agriculture, La Trobe University, Bundoora, Victoria, Australia.
R J
RJ
Xu
P D
PD
Cranwell
D000818:Animals; D000831:Animals, Newborn; D005260:Female; D005755:Gastrins / Q000097:blood / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D011498:Protein Precursors / Q000097:blood / Q000378:metabolism; D013552:Swine
D005755:Gastrins; D011498:Protein Precursors; C013706:big gastrin; C013550:gastrin 17