title: Effects of Lead in Various Preparatory Stages ofNagabhasmaon Function and Histopathology of Cornu Ammonis of Hippocampus.
abstract: BACKGROUND
  Heavy metals are frequently used in the preparations of traditional/folk medicines. One such preparation inAyurvedaisNagabhasma, in which lead is the main ingredient. Lead is non-essential element to the human body and is known toxic substance to many organ systems. However, it is claimed that, the highly toxic metallic lead will be converted into health beneficial organo-metallic compound when raw lead is subjected to various traditional methods of purification during preparation as mentioned in the ancient medicinal system.
  
  
  OBJECTIVE
  The present study is designed to evaluate the effect of such detoxification of lead in various stages of authentically preparedNagabhasmaon the learning and memory.
  
  
  METHODS
  Using half of the human equivalent doses of traditionally preparedNagabhasma, at intermittent stages of its preparation were fed orally to healthy Wistar rats for 30 days. After treatment, the immediate effect and residual effect after 2 months was evaluated by subjecting them to passive avoidance test. Then rats were sacrificed and hippocampus was collected for histopathological evaluation.
  
  
  RESULTS
  Pure lead treated animals showed deficit in learning and memory which is indicated by spending more time in the dark compartment in passive avoidance test. However, animals treated with stage 1 to 4Nagabhasmashowed gradual increase in the memory and learning. This observation is substantiated by the findings of the histopathology of the Cornu Ammonis (CA) region of hippocampus.
  
  
  CONCLUSIONS
  The results of the present study indicate that, the metallic toxicity of the lead used in the preparation of bhasma was gradually decreased from stage 1 to stage 4 of preparation. Therefore, the traditional way of preparing the metallic bhasma is very critical in eliminating the possible health hazardous metallic lead toxicity.
authors.affiliation: Senior Grade Lecturer Department of Anatomy, Kasturba Medical College, Manipal University , Manipal, Karnataka, India .
authors.forename: Lydia S
authors.initials: LS
authors.lastname: Quadros
authors.affiliation: Research Scholar, Department of Anatomy, Kasturba Medical College, Manipal University , Manipal, Karnataka, India .
authors.forename: Hemalatha
authors.initials: H
authors.lastname: Bangera
authors.affiliation: Department of Anatomy, Kasturba Medical College, Manipal University , Manipal, Karnataka, India .
authors.forename: Sushma R
authors.initials: SR
authors.lastname: Kotian
authors.affiliation: Professor and Chairperson, Department of Anatomy, RAK College of Medical Sciences , Rakmhsu, Ras Al Khaimah, UAE .
authors.forename: Kumar M R
authors.initials: KM
authors.lastname: Bhat
keywords: Ayurveda; Hippocampus; Lead; Passive avoidance test