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.
Up to 40 pg/ml
Neurokinin A is measured by direct radioimmunoassay.
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.
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.
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.
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.) contact the Institute for requirements and special handling.
Ship specimens frozen in dry ice.
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