title: Secretion of total solids (solutes) in the saliva of long-term tobacco users.
abstract: BACKGROUND
  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.
  
  
  METHODS
  Subjects of the study were divided into smokers, pan (tobacco-betel-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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Physiology, Khyber Medical College, Peshawar, Pakistan. gjillanikhan@yahoo.com
authors.forename: Ghulam Jillani
authors.initials: GJ
authors.lastname: Khan
authors.forename: Rashid
authors.initials: R
authors.lastname: Mahmood
authors.lastname: Ihtesham-ul-Haq
authors.lastname: Salah-ud-Din
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D019343:Citric Acid / Q000008:administration & dosage; D006801:Humans; D008297:Male; D009538:Nicotine / Q000008:administration & dosage; D010865:Pilot Projects; D012463:Saliva / Q000378:metabolism*; D013997:Time Factors; D014029:Tobacco Use Disorder / Q000378:metabolism*
chemical_list: D019343:Citric Acid; D009538:Nicotine