Browsing by Author "Montoya, Eladio"

Three days after a single injection of streptozotocin rats showed hyperglycemia, hyperketonemia and hypoinsulinemia. Body and liver weights were reduced and the concentration of DNA-P, phospholipid-P, proteins and acetyl-CoA in the liver was augmented, while the concentration of glycogen and citric acid in these animals compared with the controls which did not receive the drug was decreased. After 48 h starvation, blood glucose remained higher in the streptozotocin-treated animals, while circulating ketones and insulin were not different from those in the controls. With the exception of body and liver weights, which were lower, and of liver DNA-P, which was higher than when fed, neither of the other parameters studied in the s:reptozotocin treated animals changed with fasting, while the response in the c0ntrols was normal; The incapacity of increasing the postprandial insulin secretion in these animals may contribute to the metabolic alterations found in the fed state.

I. Thyroidectomized rats inj~-cted daily with 0, 0.1, 2 or 251'1! of L•lhyroxineilOOg body wt. were compared with intact controls. [n plasma, the protein-bound iodine was decreased in the rats given the O or 0.1 ,,g do~s and increased in those given the 2Sµg do~e. 2. Blood glucose Jc~rea,ed in those ~iven 21111, a11J was augmtn1~d in those given 2514g, and ketone bodies were the sam, in all the groups. 3. Plasn.a in~ulin was lowest in the rats given the O or 0.1 µg doses and was highe,t in those given the 2 or 25;,a do!cs of thyroxine. 4. After 48h stal"\·ation, the decrea~ in blood gh,cos, and increase in ketone bodies observed in oil the groups was grearest in the group not suprlemerited with thyro,i;inc. 5. Plasma insulin concentrations remained at the value for fed animals in the rats given the 25µg dose of thyroxine but decreased in the other groups. 6. In fed animals, concentrations of hepatic DNA P, citrate, total farty acids and ace1yl-CoA were similar in all the groups, and glyc()gen "as low only in the rats given the 2Srg dose of thyroxine. 7. After 48h starvation, liver DNA P, total fatty acids and acetyl-CoA increased in all the j1!roups, except in the rats given the 25rg dose, where both total fatty acids and acctyl-CoA remained al the value for fed animals. Liver citrate did not change in the groups given lhe O or 251•& doses of thyroxine, but decreased in the other groups. 8. The results arc discussed in relalion to the regulation of intermediary metabolism in hypo- and hyper-thyroidism.

During the second and third day after the intraperitoneal injection of 65 mg/kg of streptozotocin to rats the daily urinary excretion of urea, ammonia and ketone bodies is significantly elevated over levels seen in control rats. The streptozotocin treated rats show polyuria but the excretion of urinary creatinine did not differ from that in the controls. Fasted animals showed no significant differences between streptozotocin treated animals and control groups in all parameters measured. The results have been related with the in vi'fo utilization of aminoacids in diabetes to maintain elevated liver and renal gluconeogenesis.