Hemodynamic effects of calcitonin in the normal rat

Calcitonin (CT) was administered acutely (IV 4-8 U/kg) and chronically (SC 2 U/kg/day x 150 day) to normal male rats. Measurements included heart rate (HR), mean blood pressure (MBP), cardiac index (CI), peripheral vascular resistance (PVR), and stroke volume index (SVI). The MBP was higher in CT rats examined under pentobarbital anesthesia. Upon awakening from anesthesia, rats chronically on CT exhibited impaired recovery of CI and SVI. Hemodynamic effects were not seen in rats acutely treated with CT. Heart weight was unchanged in chronic treatment with CT. Therefore, CT had minimal hemodynamic effects in the normal male rat.