Isolation and characterization of substance P, substance P 5-11, and substance K from two metastatic ileal carcinoids.
Using an antiserum directed at the COOH-terminus of tachykinins, we have examined postmortem tissue from two cases of metastatic ileal carcinoid for the presence of tachykinin-like immunoreactivity. The vast majority of the immunoreactive tachykinin-like material eluted from a Sephadex G-50 column as two peaks at positions corresponding to molecular weights of 1300 and 850. The 1300 dalton peak was resolved by reverse-phase-HPLC into two components which by Edman sequencing, amino acid analysis, and fast atom bombardment (FAB)-mass spectrometry criteria, were identified as substance P and substance K. The 850 dalton peak was also resolved on RP-HPLC into two peaks which were resistant to Edman degradation but from amino acid analysis and FAB-mass spectrometry criteria were identified as pyro-Glu-substance P 5-11 and oxidized pyro-Glu-substance P 5-11. In control experiments substance P 5-11 was converted to pyro-Glu-substance P 5-11 during the extraction procedure. Both tumors also contained a minor immunoreactive peak which eluted from a Sephadex G-50 sizing column at a position corresponding to a molecular weight of 4000 which probably represents neuropeptide K. These results suggest that beta-preprotachykinin is preferentially expressed in carcinoid tumors and that substance K may also play a role in the carcinoid syndrome.
Roth
K A
KA
Makk
G
G
Beck
O
O
Faull
K
K
Tatemoto
K
K
Evans
C J
CJ
Barchas
J D
JD
D000595:Amino Acid Sequence; D002276:Carcinoid Tumor / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007078:Ileal Neoplasms / Q000032:analysis*; D013058:Mass Spectrometry; D009362:Neoplasm Metastasis; D009419:Nerve Tissue Proteins / Q000302:isolation & purification*; D015288:Neurokinin A; D010446:Peptide Fragments / Q000302:isolation & purification*; D013373:Substance P / Q000302:isolation & purification*; D015320:Tachykinins
D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D015320:Tachykinins; D013373:Substance P; C031661:substance P (5-11); D015288:Neurokinin A