Growth factor and receptor mRNA expression in the intestine of horses with large colon volvulus: a pilot study.
BACKGROUND
Growth factors (GF) are important for maintenance and repair of intestinal mucosal structure and function, but there have been no studies investigating growth factor (GF) or growth factor receptor (GF-R) mRNA expression in the intestine of horses with large colon volvulus (LCV).


OBJECTIVE
(1) To determine mRNA expression for epidermal growth factor (EGF), EGF receptor (EGF-R), insulin-like growth factor-I (IGF), IGF receptor (IGF-R), vascular endothelial growth factor (VEGF) and VEGF receptor (VEGF-R) in the intestine of horses with an LCV compared to normal intestine. (2) To measure the correlation between histological intestinal injury and mRNA expression.


METHODS
In 5 horses, samples were collected from the mid-jejunum (small intestine, SI), pelvic flexure (PF) and right dorsal colon (RDC) prior to creation of the LCV (NORM), 1 h following creation of the LCV (ISCH) and 1 h following correction of the LCV (REPER). In 2 clinical cases of LCV, samples were collected from the PF and RDC. Samples were assessed histologically for the amount of intestinal injury. The mRNA expressions of growth factors and receptors were determined using qRT-PCR.


RESULTS
VEGF and VEGF-R mRNA expression was greater in horses with an LCV compared to NORM. Expression of IGF-R mRNA increased in the SI during ISCH and REPER.


CONCLUSIONS
The increase compared to NORM in VEGF and VEGF-R mRNA expression in horses with LCV may be important in early intestinal healing and may also explain, in part, the increase in vascular permeability in horses with a LCV. Expression of IGF and IGF-R in the SI warrants further investigation and may be important for understanding post operative complications in horses with SI lesions.
Southwood
L L
LL
New Bolton Center, University of Pennsylvania, 382 W. Street Rd, Kennett Square, Pennsylvania 19348, USA.
Lindermann
J
J
Zarucco
L
L
Driessen
B
B
Olander
H
H
Habecker
P
P
Birks
E K
EK
Frisbie
D D
DD
D000818:Animals; D003108:Colonic Diseases / Q000235:genetics / Q000378:metabolism / Q000662:veterinary*; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D006734:Horse Diseases / Q000235:genetics / Q000378:metabolism*; D006736:Horses; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D045822:Intestinal Volvulus / Q000235:genetics / Q000378:metabolism / Q000662:veterinary*; D008297:Male; D010865:Pilot Projects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D017526:Receptor, IGF Type 1 / Q000235:genetics / Q000378:metabolism; D017978:Receptors, Growth Factor / Q000235:genetics / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary; D042442:Vascular Endothelial Growth Factors / Q000235:genetics / Q000378:metabolism
D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D017978:Receptors, Growth Factor; D042442:Vascular Endothelial Growth Factors; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D066246:ErbB Receptors; D017526:Receptor, IGF Type 1; D040262:Receptors, Vascular Endothelial Growth Factor