Ageing changes in the nucleic acid and protein content of the liver of the garden lizard, Calotes versicolor

Abstract

The relative DNA content (mg/g wet wt.) of the lizard liver declined sharply during postnatal stage remaining almost constant during the laterhalf of the life-span. The total DNA (mg/whole liver wet wt.) was found to increase with increasing bodyweight. The relative RNA content (mg/g wet wt.) reached the peak level at 16 g body weight and declined thereafter. The total RNA (mg/whole liver wet wt.) showed the same tendency as observed for total DNA. The relative protein content (mg/g liver wet wt.) showed the highest concentration at about 30 g bodyweight and remaining constant thereafter. When expressed on the basis of DNA (mg protein/mg DNA) the protein content also reached a peak level at about 30 g body weight but showed decline thereafter. The total protein (mg/whole liver wet wt.) indicated a steady rise with increasing age but at much slower rate beyond 50 g body weight. The RNA/ DNA ratio was highest at about 16 g body weight and declined thereafter. The RNA/Protein ratio also showed the similar trend.