Gamma radiation affects active electrolyte transport by rabbit ileum. II. Correlation of alanine and theophylline response with morphology
The response of ileal segments isolated from rabbits to an actively transported amino acid and a secretagogue was evaluated following exposure to 10 Gy whole-body gamma irradiation. The ability of ileal segments to respond to the actively transported amino acid, alanine, was not significantly diminished until 96 h postexposure. Decreased responsiveness to the secretagogue, theophylline, occurred earlier at 72 h. These effects did not appear to be accounted for by decreased food intake of irradiated animals alone. Examination of intestinal morphological changes with respect to these changes in electrolyte transport revealed that decreased amino acid transport coincides with loss of intestinal villi. Although a morphological correlate of decreased secretory response was not as striking as that for absorption, the theophylline response appeared to decline concomitant with the appearance of increased mitotic activity in the intestinal crypts. The results of this study indicate that, following a dose of 10 Gy, the inability of these tissues to respond to amino acids is due to a loss of mature villus absorptive cells subsequent to denudation of the intestinal mucosa. There appeared to be little impairment of cell membrane transport processes for alanine. In contrast, the decreased secretory response could not be correlated with the disappearance of any one cell type and perhaps results from increased proliferation in the crypts at the expense of differentiation.
- Research Organization:
- Armed Forces Radiobiology Research Institute, Bethesda, MD (USA)
- OSTI ID:
- 5986519
- Journal Information:
- Radiat. Res.; (United States), Vol. 117:3
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ALANINES
MEMBRANE TRANSPORT
SMALL INTESTINE
MORPHOLOGICAL CHANGES
BIOLOGICAL RADIATION EFFECTS
CELL PROLIFERATION
ELECTROLYTES
GAMMA RADIATION
MUCOUS MEMBRANES
RABBITS
RADIATION INJURIES
THEOPHYLLINE
WHOLE-BODY IRRADIATION
AMINO ACIDS
ANIMALS
AROMATICS
AZAARENES
BIOLOGICAL EFFECTS
BODY
CARBOXYLIC ACIDS
CARDIOVASCULAR AGENTS
DIGESTIVE SYSTEM
DRUGS
ELECTROMAGNETIC RADIATION
EXTERNAL IRRADIATION
GASTROINTESTINAL TRACT
HETEROCYCLIC COMPOUNDS
INJURIES
INTESTINES
IONIZING RADIATIONS
IRRADIATION
MAMMALS
MEMBRANES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANS
PURINES
RADIATION EFFECTS
RADIATIONS
VASODILATORS
VERTEBRATES
XANTHINES
560152* - Radiation Effects on Animals- Animals