Angiotensin-converting enzyme inhibition increases glucose-induced insulin secretion in response to acute restraint
Article first published online: 26 NOV 2012
© 2012 The Authors Clinical and Experimental Pharmacology and Physiology © 2012 Wiley Publishing Asia Pty Ltd
Clinical and Experimental Pharmacology and Physiology
Volume 39, Issue 12, pages 1034–1037, December 2012
How to Cite
Schweizer, J. R., Miranda, P. A., Fóscolo, R. B., Lemos, J. P., Paula, L. F., Silveira, W. C., Santos, R. A., Pinheiro, S. V., Coimbra, C. C. and Ribeiro-Oliveira, A. (2012), Angiotensin-converting enzyme inhibition increases glucose-induced insulin secretion in response to acute restraint. Clinical and Experimental Pharmacology and Physiology, 39: 1034–1037. doi: 10.1111/1440-1681.12021
- Issue published online: 26 NOV 2012
- Article first published online: 26 NOV 2012
- Manuscript Accepted: 7 OCT 2012
- Manuscript Revised: 1 OCT 2012
- Manuscript Received: 10 JUN 2012
- There is increasing evidence suggesting involvement of the renin–angiotensin system (RAS) in carbohydrate metabolism and its response to stress. Thus, the aim of the present study was to evaluate the effects of chronic inhibition of the RAS on glucose and insulin levels during acute restraint stress.
- Male Holtzman rats were treated with 10 mg/kg per day enalapril solution or vehicle for 14 days. After 14 days, rats were divided into three experimental groups: enalapril + restraint (ER), vehicle + restraint (VR) and enalapril + saline (ES). Rats in the restraint groups were subjected to 30 min restraint stress, whereas rats in the ES groups were given saline infusion instead. Blood samples were collected at baseline and after 5, 10, 20 and 30 min restraint stress or saline infusion.
- After restraint, a hyperglycaemic response was observed in the ER and VR groups that peaked at 20 and 10 min, respectively (P < 0.05 compared with baseline). The area under the glucose curve was markedly increased in the ER and VR groups compared with that in the ES group (P < 0.05 for both). Importantly, restraint induced a marked increase in insulin secretion in the ER group compared with only a mild elevation in the VR group; insulin secretion in both groups peaked at 20 min (P < 0.05 compared with baseline). Analysis of the area under the insulin curve confirmed an increase in insulin secretion in the ER compared with the VR and ES groups (P < 0.05 for both).
- The results of the present study reinforce that the RAS is involved in modulating responses to stress and suggest that RAS inhibition with enalapril may increase glucose-induced insulin secretion in response to acute restraint.