Activity of acid and alkaline phosphatases extracted from the liver of bull frog (Lithobates catesbeianus) tadpoles during metamorphosis

Abstract

Metamorphosis is a crucial step in the amphibian's development, characterized by a series of events, which enable the tadpoles to change from aquatic to terrestrial environments. The morphological events are visible, while physiological and biochemical are difficult to be demonstrated. The liver is an important organ in animal metabolism, making the processing and distribution of nutrients through the bloodstream to other organs and tissues. Phosphorus is essential for the implementation of adaptive changes. During the animal's life and metamorphosis, the acid phosphatase present in the liver acts as an indicator of lysosomal activity, while alkaline phosphatase, a membrane enzyme, can act as an ATPase and in the detoxification of phosphate esters generated during metabolism. The animals will be anesthetized on ice, decapitated, the livers will be removed and homogenized, then centrifuged at 10.000 rpm for 10 minutes at 4°C. The supernatant obtained will be filtered through glass wool, then aliquoted, frozen in liquid nitrogen, and stored at -70°C for later analysis of enzyme activity and determination of protein concentration. Since the liver is responsible to perform various important synthesis processes and the is a lack of information about the functions of acid and alkaline phosphatases present in the organ, this study aims to analyze the activities of both enzymes involved in the metabolism of phosphorus during the metamorphosis of Lithobates catesbeianus tadpoles.(AU)