Sh. Adams et J. Odle, PLASMA BETA-HYDROXYBUTYRATE AFTER OCTANOATE CHALLENGE - ATTENUATED KETOGENIC CAPACITY IN NEONATAL SWINE, The American journal of physiology, 265(4), 1993, pp. 180000761-180000765
Suckling neonatal pigs (NP, 24 h old) do not exhibit elevated blood ke
tone bodies (KB). Mature swine have relatively high KB under certain c
onditions, suggesting an ontogeny of ketogenesis. Thus we evaluated th
e hypothesis that NP possess a relatively attenuated ketogenic capacit
y vs. weaned pigs (WP) and mature pigs (MP). Fasted animals were given
an intraperitoneal dose of octanoate (C8), and plasma beta-hydroxybut
yrate (beta-OHB) and C8 were monitored over 180 min. Newborn (NR, 24 h
old) and mature rabbits (MR, >1 yr old) were also compared. Linear re
gressions of plasma beta-OHB (muM) vs. plasma C8 (muM) were calculated
for C8 <1,000 muM. There was a significant linear relationship of bet
a-OHB regressed against C8 in all ages of pigs (P < 0.001) and in NR (
P = 0.024). The slope for NP (0.08) was one to two orders of magnitude
below slopes for older pigs (WP = 1.19 and MP = 0.78, P < 0.01 vs. NP
), NR (6.97, P < 0.05), and MR (4.04, NS). The beta-OHB peak in NP (40
.9 +/- 4.4 muM) was 1-8% of the maxima in other animals (P < 0.05) des
pite a C8 maximum (2.3 +/- 0.3 mM) similar to that of WP (1.9 +/- 0.7
mM) and MR (2.9 +/- 1.2 mM) (P > 0.05, NS). The data are consistent wi
th the hypothesis that NP have a poor capacity for ketogenesis.