Carbohydrate hydrolysis, transport and utilization were investigated in rats exposed to diminished motor activity for 90 days. Glycemic curves were examined using provocative tests with equivalent quantities (1.5 g/kg
body weight) of poly-, oligo- and
monosaccharides (
starch,
maltose,
glucose). Simultaneously, carbohydrases were measured in the homogenates of the pancreas, duodenal mucosa and small intestine as well as radioimmune
insulin and
glucagon were determined in blood. In the course of
hypokinesia carbohydrate hydrolysis, transport and utilization varied in a different manner. At the beginning of exposure the activity of carbohydrases responsible for
carbohydrate hydrolysis in the cavity and membranes increased which was accompanied by
hyperglycemia and rapid utilization of
carbohydrates. This is associated with nonspecific reactions to
hypokinesia and higher requirements of the body for the energy substrate. By
hypokinesia day 30
carbohydrate hydrolysis and transport were inhibited,
hypoglycemia developed but
glucose utilization remained unchanged. At a later stage of exposure the system of
carbohydrate hydrolysis and transport showed an adaptive reaction; inhibition of pancreatic
amylase was accompanied by accelerated
enzyme transport in the small intestine and
glucose resorption. In this situation the glycemic curves became extended suggesting a delay in
glucose utilization. The latter was induced by changes in the endocrine compartment of the pancreas.