Effects of oral arginine and glutamine on radiation-induced injury in the rat.
BACKGROUND
Exposure of the abdominal region to ionizing radiation is associated with serious untoward symptoms of intestinal dysfunction and some reports indicate that nutrient supplements may reduce these adverse effects. This study was designed to investigate the possible beneficial effects of oral arginine or glutamine supplementation on the radiation-induced tissue injury.


METHODS
Rats were given one of three feeding regimens: standard diet and water (control group), diet and water containing 2% arginine (arginine group), diet and water containing 2% glutamine (glutamine group) for 3 days prior to radiation. All rats were then subjected to a single does of 1100 cGy to the abdomen. Several serum biochemical parameters and the histologic alterations in different segments of gastrointestinal tract and liver were measured 4 days after irradiation.


RESULTS
All the arginine-fed rats developed diarrhea on Day 4 postirradiation, compared to 71% incidence in control rats and 86% in glutamine-fed rats. Serum levels of aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in the arginine group were markedly higher than those in other groups. On histological examination, radiation caused more serious damage to various segments of intestine in the arginine-fed rats compared to rats on other feeding regimens.


CONCLUSIONS
These observations seriously question the beneficial effects of arginine and glutamine supplementations on radiation-induced tissue injury.
Hwang
Jing-Min
JM
Department of Radiation Oncology, Tri-Service General Hospital, Republic of, Taipei, Taiwan, Republic of China.
Chan
De-Chuan
DC
Chang
Tzu-Ming
TM
Tsao
Tang-Yi
TY
Tsou
Shung-Sheng
SS
Lu
Ruey-Hwa
RH
Tsai
Lih-Min
LM
D000284:Administration, Oral; D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000494:pharmacology*; D001219:Aspartate Aminotransferases / Q000097:blood; D003967:Diarrhea / Q000209:etiology*; D019587:Dietary Supplements; D005973:Glutamine / Q000008:administration & dosage / Q000494:pharmacology*; D007410:Intestinal Diseases / Q000150:complications / Q000517:prevention & control; D007422:Intestines / Q000187:drug effects* / Q000473:pathology / Q000528:radiation effects*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008099:Liver / Q000187:drug effects* / Q000473:pathology / Q000528:radiation effects*; D008107:Liver Diseases / Q000097:blood / Q000150:complications / Q000517:prevention & control; D008297:Male; D023421:Models, Animal; D011833:Radiation Injuries, Experimental / Q000150:complications / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley
D005973:Glutamine; D001120:Arginine; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases