TOXICOPATHOLOGICAL IMPACT OF SUB-LETHAL CONCENTRATION OF LEAD NITRATE ON THE AERIAL RESPIRATORY ORGANS OF ‘MURREL’ CHANNA STRIATA (BLOCH, PISCES)

Sub-lethal toxicity of lead nitrate solution (46.25mg/l, 5% of 96h lc50 value) on the air-breathing organ(suprabranchial chamber) of channa striata was analysed for 60 days. because air-breathing organs of c.striata remain in direct contact with waterborne xenobiotics, any change in the aquatic ecosystem wasdirectly reflected in them. concentration of lead accumulation in the air-breathing organ fluctuated atdifferent stages of exposure. due to extensive secretory activity, the mucous cells very often gotexhausted and disappeared followed by their regeneration. this causes periodic fluctuations in the densityof the mucous cells. a significant increase in the gross dna contents in relation to the respective controlis noticed at many stages of exposure. increases in the rna and protein contents with simultaneousincrease in the mucogenic activity of the mucous cells were also observed. the total lipid contents alsoshowed a periodic fluctuation in their concentration.