Biomaterial Database

Calcium metabolism in bullfrog tadpoles (Rana catesbeiana). 1980

G F Baldwin, and P J Bentley

Non-feeding bullfrog (Rana catesbeiana) tadpoles can maintain their body Ca concentration in artificial pond waters containing a range of Ca concentrations. The rate of uptake of 45Ca increases when the tadpoles are pre-adapted to a low-Ca pond water and declines when they are pre-adapted to high Ca. Measurement of drinking rate shows that drinking could account for only 5% of the influx. From in vitro experiments, it is estimated that about 70% of the influx occurs accoss the gills, and about 25% through the skin. Calcitonin decreases accumulation of 45Ca while 1,25-(OH)2 vitamin D3 increases it; parathyroid hormone was without effect. Efflux of 45Ca was unchanged by calcitonin or parathyroid hormone.

UI	MeSH Term	Description	Entries
D007408	Intestinal Absorption	Uptake of substances through the lining of the INTESTINES.	Absorption, Intestinal
D007814	Larva	Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.	Maggots,Tadpoles,Larvae,Maggot,Tadpole
D011892	Rana catesbeiana	A species of the family Ranidae (true frogs). The only anuran properly referred to by the common name "bullfrog", it is the largest native anuran in North America.	Bullfrog,Bullfrogs,Rana catesbeianas,catesbeiana, Rana
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.