Melanocyte Stimulating Hormone, Beta (b-MSH)

• ISI Order Code:

  MSH BETA

• CPT Code:

  83519

Clinical Significance:

b-Melanocyte Stimulating Hormone is a 22 amino acid peptide produced from metabolism of Proopiomelanocortin.  One of the fragments of Proopiomelano-cortin is b-Lipotropin which is further fragmented to form g-Lipotropin and b-Endorphin.  g-Lipotropin is then metabolized to form b-Melanocyte Stimulating Hormone. The major biological property of b-Melanocyte Stimulating Hormone is hyperpigmentation.  It also stimulates Aldosterone secretion and is excreted by the placenta.  b-Melanocyte Stimulating Hormone is the major melanocortin in man.  b-Melanocyte Stimulating Hormone has been found in elevated levels in cases of ectopic ACTH tumors and also in some non-endocrine tumors.  b-Melanocyte Stimulating Hormone has also been shown to accentuate attention resulting in improved memory, heightened arousal and increased fear.

• Reference Range:

  Up to 150 pg/mL

• Procedure:

  b-Melanocyte Stimulating Hormone is measured by direct radioimmunoassay.

• Expected Turnaround Time:

  7–10 Business Days

Turnaround time is defined as the usual number of days from the date of receipt of a specimen for testing to when the result is released to the ordering facility.

• Report:

  Sample Report

Patient Preparation:

Patient should not be on any Steroid, ACTH, or hypertension medication, if possible, for at least 48 hours prior to collection of specimen.  Morning, fasting specimens are preferred; non-fasting specimens are acceptable.

Specimen Collection:

3mL EDTA plasma should be collected and separated as soon as possible. Freeze specimen immediately after separation. Minimum specimen size is 1mL.

Serum is no longer accepted for the ISI assay.

• Rejection Criteria:

  Gross hemolysis/lipemia/icteric

Special Specimens:

For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.

Shipping Instructions:

Ship specimens frozen in dry ice.

References:

1. DB Seifer and RL Collins.  Current Concepts of b-Endorphin Physiology in Female Reproductive Dysfunction.  Clinical Chemistry 54: 757-771, 1990.

2. Y Hirata, N Sakamoto, S Matsukura, and H Imura.  Plasma Levels of b-Msh and ACTH during Acute Stresses and Metyrapone Administration in Man.  Journal of Clinical Endocrinology and Metabolism  41: 1092, 1975.