Test Overview

Test Methodology

Direct Enzyme Immunoassay (EIA)

Test Usage

Growth Hormone Releasing Hormone is a 44 amino acid peptide produced primarily by the hypothalamus. It is a neurohumoral control for adenohypophyseal secretion of Growth Hormone. Other hypothalamic hormones have a stimulatory effect on pituitary hormones, but Growth Hormone Releasing Hormone has no known effect on other pituitary hormones. Somatostatin is the inhibitory counterpart of Growth Hormone Releasing Hormone. Growth Hormone Releasing Hormone has structural similarities with the Secretin-Glucagon family of gastrointestinal hormones. Growth Hormone Releasing Hormone has been isolated from pancreatic Islet Cells and various cancer tumor cells.

Reference Range*

Levels of IR-GH-RH
Baseline range: 5-18 pg/mL
Levels in GH-RH Dysfunction:
Patients with acromegaly: up to 200 pg/mL
Patients with small cell lung carcinoma: up to 50 pg/mL
GH-RH secreting tumors: 200-10,000 pg/mL

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details

Days Test Performed

Monday - Friday

Analytic Time

5 - 9 days

Soft Order Code





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Laboratory Reference

Mayo FIRGH (90161) (Interscience)

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Specimen Requirements

Offsite Collection Instructions

Collect specimen in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and freeze.


Yellow Top Tube

Normal Volume

3 mL serum

Minimum Volume

1 mL serum

Additional Information

Test sent to Mayo Medical Laboratories; performed by Interscience Institute.

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Fee Codes

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