Gluconeogenesis activation after intravenous angiotensin II in freely moving rats.

Intravenous (IV) administration of angiotensin II (0.95 nmol/100 g body weight) produced a marked increase in plasma glucose of 20 h fasted rats. To investigate the possibility of a stimulation of gluconeogenesis, conscious unrestrained rats were continuously infused with [14C]bicarbonate, 60 microl/min (0.18 microCi/min), and label incorporation into circulating glucose was determined before and after angiotensin injection. The rate of 14C incorporation into blood glucose of fed rats increased significantly after angiotensin II administration, a 279% increase after 20 min (P < 0.01). In conclusion, the results of the present study show that the hyperglycemia induced by intravenous (IV) administration of angiotensin II is accompanied by an activation of gluconeogenesis, as evidenced by a rapid and marked increase in the rate of 14CO2 incorporation into circulating glucose.