Turnaround Time: 7 - 9 days
CPT Code:


Test Type: 0.5 mL Plasma, frozen
Stability Time:




9 days

Freeze/thaw cycles

Stable x3


Determination of cAMP is useful in the clinical assessment of parathyroid function.

Cyclic adenosine-3'-5'-monophosphate (cAMP) serves as a second messenger in signal transduction of various hormones, like adrenaline, ACTH, LH, FSH, glucagon, and calcitonin. The hormone itself is the first messenger, binding to specific membrane receptors of hormone-responsive cells. This leads to the activation of an enzyme located at the inner side of the cell membrane, called adenylate cyclase, which catalyzes the synthesis of cAMP from ATP. The increased cellular level of cAMP initiates the activation of protein kinases. The determination of cAMP in urine or plasma has become more and more important in the clinical assessment of parathyroid functions. The parathyroid hormone (PTH) stimulates the synthesis of cAMP in the renal cortex and an increased secretion of cAMP. Cyclic AMP is a specific marker of circulating PTH: 90% of patients with hyperparathyroidism show increased levels of nephrogenic cAMP. The determination of cAMP is also significant for the differential diagnosis of hypercalcemia

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Collection Details:

Patient Preparation:

Patient should have no radioactive isotopes administered within 48 hours prior to venipuncture.

Collection Instructions:

Lavender-top (EDTA) tube.

Keep blood samples on ice and centrifuge as soon as possible. Separate plasma from cells and transfer to a plastic transport tube. Freeze immediately. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.