Abstract:

59Fe was incorporated in vivo into intestinal sacs prepared in control rats as well as in animals with turpentine sterile abscesses and 59Fe counts were detected in the intestinal wall, in blood, in liver, in spleen and in femur of animals, at different time intervals (20, 40 and 120 min) following i.v. injection of isoproterenol (10 μg/kg, body weight) or of (-)-propranolol (2 mg/kg, body weight). In rats without inflammation isoproterenol alone enhanced significantly iron counts in blood, spleen, liver and femur, but not in intestinal cells, whereas propranolol evoked opposite actions, the influence being more marked after 40 min, reaching maximal values at 120 min. In animals with sterile turpentine abscesses explored 40 min after injections, iron intestinal counts in turpentine, in turpentine plus isoproterenol and in turpentine plus propranolol groups were significantly lower than in normal saline injected controls (p < 0.001) and the opposite was the case at 120 min. In blood, iron counts at 20 and 40 min were higher in saline controls (p < 0.05) than in the turpentine group, whereas at 120 min, values in the turpentine plus isoproterenol group were higher than (p < 0.01) in saline injected controls with turpentine alone. Also, at all time intervals explored, iron counts in blood in the propranolol plus turpentine group were smaller (p < 0.01) than in saline injected controls or in the group with turpentine alone. At 120 min the % of 59Fe uptake in liver from turpentine plus isoproterenol animals was greater than in saline injected controls, than in turpentine alone, or than in turpentine plus propranolol rats. No differences among groups were detected in spleen or in femur. Results in rats with turpentine abscesses suggest that isoproterenol acts favoring iron transport from intestinal cells enhancing its movement into blood, whereas propranolol appears associated to the opposite action. Moreover, beta adrenoceptors appear to be involved not only during early stages of intestinal absorption but also during further distribution and final uptake by storage organs, such as the liver.