Effect of Endotoxin on Insulin-like Growth Factor-1 Expression in Small Intestine and Intrauterine Growth of Rabbit Fetus / 대한산부인과학회잡지

ABSTRACT

OBJECTIVE: New Zealand White Rabbits were utilized to determine whether fetal insulin-like growth factor-1 (IGF-1) expression in small intestine is altered in response to maternal enodotoxin administration. STUDY DESIGN: Six pregnant rabbits were intramuscularly injected with lipopolysaccharide of E. coli (serotype 055B5) 30 microgram/kg, whereas normal saline 0.3 mL/kg were injected to the other six pregnant rabbits on gestational day 25 and 26. Fetuses were harvested on gestational day 27 and were identified as favored (Fav) or runt (Runt) depending on the location in the uterus. Fetal weight and small intestinal length were recorded. Three parts of small intestine (proximal, middle and distal) were collected. Reverse transcription polymerase chain reaction (RT-PCR) was used to measure IGF-1/beta-actin mRNA densitometric band ratios. Statistical analysis was performed using paired Student's t-test and Pearson correlation test. RESULTS: The ratio of mRNA IGF-1/beta-actin was lower in endotoxin group (0.80+/-0.24, n=24) than control group (1.13+/-0.31, n=24, P0.05). CONCLUSION: In our study, maternal endotoxin administration suppressed IGF-1 production in small intestine of fetal rabbit. Endotoxin in maternal serum might be transferred to fetus through placenta and decreased production of mRNA of IGF-1 in small intestine. Further studies are warranted to investigate the correlation between intrauterine growth retardation and maternal gram negative bacterial infection.