Neurokinin A (Substance K) NYS DOH Approved tests PFI#9065

Clinical Significance:
Neurokinin A is a ten amino acid putative transmitter synthesized in the neurons it is present in.  Neurokinin A is a member of the family called Tachykinins which also include Neurokinin B, Substance P, Physalaemin, and Eledoisin.   Neurokinin A shares 6 of 10 peptide homologies with Neurokinin B even though they are produced by different genes.   Neurokinin A is also very similar in structure to Substance P and produces some of the same biological actions as Substance P.  Neurokinin A is a potent bronchoconstrictor.  In the gut, Neurokinin A is produced by the intrinsic enteric nervous system.

Reference Range:
Up to 40 pg/ml

Neurokinin A is measured by direct radioimmunoassay.

Patient Preparation:
Patient should not be on any medications that affect hypertension, gastrointestinal functions, or pain relievers, if possible, for at least 48 hours prior to collection of specimen.

Specimen Collection:
Collect 10mL blood directly into ISI’s Z-tubeTM Preservative and separate as soon as possible. Freeze plasma immediately after separation. Special Z-tubeTM Preservatives are available from ISI. Minimum specimen size is 1mL. Note: one Z-tubeTM may be shared for up to three tests. After centrifuging tube, aliqout 1mL per test in separate vials, mark with name of test and freeze.

Important Precaution:
Specimens for this assay must be collected using the Z-tube. Specimens must be shipped frozen; specimens are not stable at refrigerated or room temperatures. No other specimens are acceptable.

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.

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