Excretion of Cyclic 3', 5'-Adenosine Monophosphate in Renal Insufficiency and Primary Hyperparathyroidism after Stimulation with Parathyroid Hormone

Abstract

Cyclic 3', 5'-adenosine monophosphate (cAMP) excretion in the urine after an infusion of 100 U bovine parathyroid hormone (PTH) was studied in chronic renal failure and primary hyperparathyroidism (pHPTH). cAMP was determined by a binding protein assay. Basal excretion was 2.9 µMol/g creatinine in normal subjects, 2.3 in a group of patients with renal insufficiency and with creatinine clearance between 65 and 33 ml/min, and 0.7 and 4.9 in two groups with creatinine clearance below 25 ml/min. The increase in urinary cAMP after exogenous PTH administration was decreased in patients with renal insufficiency; the group with low basal excretion showed no response. This may be caused by secondary hyperparathyroidism (sHPTH), although other reasons for PTH resistance can not be excluded. In 7 cases of pHPTH there was a diminished increased of cAMP excretion in the urine after PTH infusion. This phenomenon might be of diagnostic value. 1 Some of the results have been represented at the 19th Symposion Deutsche Gesellschaft für Endokrinologie, Feb.28 - Mar. 3, 1973, Berlin.