Role of ultimobranchial body and corpuscle of Stannius in regulation of the plasma calcium and phosphorus levels in the teleost Heteropneustes fossilis.

Effects of NaF, CaCl2, NaCl and mammalian calcitonin on the histology of ultimo-branchial (UTB) and corpuscle of Stannius (CS) and plasma levels of calcium and phosphorus in the teleost Heteropneustes fossilis are recorded. Administration of NaF, NaCl, and mammalian calcitonin resulted in varying degree of hypolcalcaemia and hyperphosphataemia, whereas hypercalcaemia and hypophosphataemia developed during CaCl2 treatment. These treatments also produced various histological changes in UTB and CS. It is suggested that CS and UTB are involved in metabolisms of Ca and P, and in osmoregulation. Moreover, it is an important hypocalcaemic mechanism in this fish in combating hypercalcaemia.