Acute Anti-Inflammatory Effects of Salbutamol in the Rat Air Pouch Model of Inflammation

Abstract

Background: Recent studies have proven that immune and nervous systems have a bidirectional communication. Anti-inflammatory effects of β2 adrenergic receptors have been considered in recent years. Aims: The aim of this study is to investigate the effects of salbutamol on the inflammatory parameters in the rat air pouch model of inflammation. Method: Male Wistar rats were anesthetized; 20ml and 10ml of sterile air were injected subcutaneously on the back of animals on day 1 and 3 respectively. On day 6, inflammation was induced by injection of 1ml of carrageenan 1% into pouch. One milliliter of salbutamol (125, 250 & 500 µg/pouch) and salbutamol plus propranolol (500µg/pouch) in the test groups and saline in the control group were administered intra pouch at the same time as the carrageenan. After 6 hours animals were sacrificed. The pouches were flushed with PBS. Then they were opened, pouches fluid was collected in order to determine exudates volume, cells accumulation and IL-1β concentration. The granulation tissues formed were dissected out and the weight determined. Results: Leukocytes accumulation and exudates volume were decreased significantly by salbutamol 250 µg/pouch (P<0.01). The dose of 500 µg/pouch of salbutamol reduced significantly the number of leukocytes (P=0), exudates volume (P=0), granulation tissue weight (P<0.001) and IL-1β level (P<0.01). In addition there were no changes in the inflammatory parameters by co-administration of salbutamol and propranolol. Conclusion: From this study it may be concluded that salbutamol possesses anti-inflammatory property possibly through the stimulation of β-2 adrenergic receptors. This anti-inflammatory effect may be as important mechanism in asthma treatment, where inflammation also has role in the etiopathology.