Altered control of ventilation in streptozotocin-induced diabetic rats

The purposes of this study were (i) to determine if ventilatory control is altered in streptozotocin (STZ)-induced diabetic rats and (ii) to determine whether insulin treatment of diabetic rats could prevent ventilatory abnormalities. Male Sprague-Dawley rats were randomly assigned to three groups: control (n = 10), diabetic (n = 9), and diabetic treated with insulin (n = 9). The diabetic group exhibited a progressive reduction of tidal volume, minute ventilation, and CO2 production compared with the control and diabetic treated with insulin groups over the 4 week period. Furthermore, the ventilatory responses to the hypercapnic (3%, 6%, 9% CO2) and hypoxic (10% O2) gas challenges were significantly less in the diabetic rats than those of the control and diabetic and insulin treated groups by the third and fourth week. Ventilation and ventilatory responses to hypercapnia and hypoxia were similar in the control group and the diabetic treated with insulin group at the end of the study. In conclusion, uncontrolled diabetes induced in rats by STZ treatment resulted in altered control of ventilation that could be prevented by insulin therapy.