The effects of noise on cardiovascular parameters using isolated rat`s heart

Abstract

The present study was undertaken to evaluate the effect of acute and chronic high intensity noise on the isolated hearts of rats using the Langendorff apparatus by determining the effect of noise on the coronary perfusion pressure (CPP), heart rate (HR) and left ventricular diastolic pressure (LVDP), as well as to investigate its effect on plasma blood glucose concentration and lipid profile. The rats were divided into four groups and they include exposure to noise of intensity 80-100 dBA on duration of 12 hours exposure (acute effect), 8 hours daily for 20 days (chronic effect), 20 days into 3 days exposure and 2 days without 8 hours per day (intermittent effect) and the control group. Noise of 80-100 dBA was found to cause significant increase in CPP, LVDP and HR (p< 0.05) for acute and both chronic groups versus control. Plasma glucose, were significantly increased in its concentration for the acute and chronic continuous groups as compared to no noise exposure. The cholesterol, triglycerides (TG) and high density lipoprotein (HDL) had no significant difference compared to control. In the case of acute noise exposure although there is a significant elevation in the chronic continuous group. HDL level revealed significant elevation in case of chronic continuous and intermittent noise exposure (p < 0.05) when compared to control group. Correlation analysis has been done between the study groups and we found that there was a negative correlation between blood glucose and HR in acute and chronic continuous noise exposure study groups. In conclusion the present study determined that high intensity noise may have an adverse effect on cardiovascular functions and thus noise exposure should be well monitored.