Immunolocalization of epidermal growth factor (EGF) and EGF receptors in the porcine upper gastrointestinal tract.
The factors controlling growth and maturation in the porcine gastrointestinal tract are not well understood. Epidermal growth factor (EGF) is a polypeptide that has been implicated in the control of gastrointestinal tract growth, maturation, and protection in other species. Immunoreactive EGF (IR-EGF) and EGF receptors (EGF-R) were histochemically identified in formalin-fixed tissues of the upper digestive tract of 1-, 3-, 7-, 14-, 21-, and 28-day-old pigs. The ductal epithelium consistently contained IR-EGF in the parotid salivary gland of pigs of all ages and in the mandibular salivary gland in pigs greater than or equal to 7 days old. Immunoreactive EGF was detected in the mucosal epithelium of the esophagus and nonglandular portion of the stomach, and in the pancreas and liver in all pigs. Gastric gland IR-EGF was inconsistently detected in pigs less than 14 days old and was consistently observed in all older pigs. Enterocyte EGF immunoreactivity was usually weak and was variably detected in the duodenum of pigs less than or equal to 7 days old and in the jejunum of pigs less than or equal to 14 days old, but was consistently observed in older pigs. Ileal immunoreactivity was erratic. Immunoreactive EGF-R were identified in the esophageal epithelium of all pigs, and in the nonglandular gastric and glandular gastric mucosa of all pigs, except for two 7-day-old pigs and one 7-day-old pig, respectively. Immunoreactive EGF-R were detected in the duodenal, jejunal, and ileal enterocytes of pigs of all ages examined.
Jaeger
L A
LA
Department of Anatomy, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.
Lamar
C H
CH
D000818:Animals; D004064:Digestive System / Q000737:chemistry*; D004815:Epidermal Growth Factor / Q000032:analysis* / Q000276:immunology; D066246:ErbB Receptors / Q000032:analysis* / Q000276:immunology; D004947:Esophagus / Q000737:chemistry; D005260:Female; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000737:chemistry; D008099:Liver / Q000737:chemistry; D008297:Male; D010179:Pancreas / Q000737:chemistry; D012469:Salivary Glands / Q000737:chemistry; D013270:Stomach / Q000737:chemistry; D013552:Swine / Q000254:growth & development*
D004815:Epidermal Growth Factor; D066246:ErbB Receptors