Secretion of total solids [solutes] in the saliva of long-term tobacco users

It is generally believed that repeated exposure of a receptor to a stimulus results in inactivation [suppression or adaptation] of the receptor .Most of the methods of tobacco use are linked to the oral cavity where the taste receptors, a primary site for stimulation of salivary secretion, are constantly exposed to tobacco for long time. The present study was designed to document changes in salivary concentration of total solids in response to this effect in chronic tobacco users, if any. Subjects of the study were divided into smokers, pan [tobaccobetel- lime quid] chewers, niswar [moist oral snuff] dippers and non tobacco users as controls. The saliva of each subject was collected under resting condition and following application of crude nicotine and citric acid solutions to the tip of his tongue. After stimulation with nicotine all groups showed a decrease in the total solids concentration but the decrease was not significant in any group. After stimulation with citric acid, further decrease was seen in all groups but it was also insignificant statistically. We conclude that the total solids concentration decreases with the increase in salivary flow rates [and vice versa] in long-term tobacco users, salivary reflex is not adversely affected by long-term use of tobacco and this observation is not much different from that in non users

Effect of noise on heart rate

The objective of the study was to observe the effect of short-term noise on heart rate. One Hundred and seventeen [117] medical students were selected as subjects. Subjects having normal resting heart rate and blood pressure were included in the study. Subjects with, hearing defect were excluded from study. Auditory aquity was confirmed by audiometry before the start of experiment for each subject. A noise of a 90 dB intensity and 4000Hz frequency was produced for 10 minutes. Heart rate was recorded before, during and after exposure to noise. Heart rate increased in 104 [88.9%] subjects, with an average rise of 8.938+ 1.037. In 73 subjects [70.19%] it came back to basal level within 02 minutes. Increase in heart rate was observed in more number of males as compared to females; however, the difference was statistically insignificant. Heart rate increases during exposure to noise