PMID- 8102327
OWN - NLM
STAT- MEDLINE
DCOM- 19930913
LR  - 20190813
IS  - 0300-0664 (Print)
IS  - 0300-0664 (Linking)
VI  - 39
IP  - 1
DP  - 1993 Jul
TI  - Peptide alpha-amidation activity in human plasma: relationship to gastrin 
      processing.
PG  - 51-8
AB  - OBJECTIVE AND DESIGN: C-terminal amidation is an essential processing step 
      towards bioactivation of many peptides including gastrin. This reaction is 
      catalysed by peptidylglycine alpha-amidating mono-oxygenase (PAM, EC 1.14.17.3) 
      which converts the glycine extended precursors on their carboxyl termini to the 
      des-glycine amidated peptide products. In the case of gastrin, most of the 
      amidation is thought to occur in the antrum. However substantial quantities of 
      glycine extended gastrin and PAM are present in plasma. It is unclear whether 
      circulating PAM reflects the secretory activity of the gastrin secreting cell or 
      whether PAM is involved in the postsecretory processing of gastrin. The aim of 
      the present study was to relate the circulating amidation activity to the plasma 
      concentrations of glycine extended and amidated gastrins. PATIENTS AND 
      MEASUREMENTS: Plasma PAM, gastrin-amide and gastrin-gly were measured in subjects 
      with different gastrin secretory status: healthy subjects basally and following a 
      meal, members of families with multiple endocrine neoplasia type 1 (MEN-1) with 
      normal and high plasma gastrin, and patients with hypergastrinaemic atrophic 
      gastritis. RESULTS: Patients with MEN-1 and hypergastrinaemia tended to have a 
      higher plasma PAM activity than MEN-1 subjects with normal circulating G-NH2 
      indicating a cosecretion of hormone and PAM. However in contradistinction to 
      patients with medullary thyroid carcinoma, PAM activity does not appear to be a 
      useful tumour marker of gastrinoma. Hypergastrinaemia from a non-tumour source 
      (hypergastrinaemic non-atrophic gastritis) was associated with a lower plasma PAM 
      activity than in normal subjects and may reflect the secretion of a greater 
      proportion of already amidated gastrin. In general, there was no relationship 
      between plasma PAM activity and the ratio of amidated to non-amidated gastrin 
      suggesting that circulating PAM was not involved in the amidation of gastrin. 
      Feeding increased circulating gastrin but had no effect on plasma PAM activity. 
      CONCLUSION: The results support the view that gastrin is amidated at the site of 
      its synthesis and that hypergastrinaemia is associated with elevated plasma 
      amidating enzyme activity only when the gastrin originates from tumour sources.
FAU - Kapuscinski, M
AU  - Kapuscinski M
AD  - Department of Surgery, University of Melbourne, Austin Hospital, Victoria, 
      Australia.
FAU - Green, M
AU  - Green M
FAU - Sinha, S N
AU  - Sinha SN
FAU - Shepherd, J J
AU  - Shepherd JJ
FAU - Shulkes, A
AU  - Shulkes A
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Clin Endocrinol (Oxf)
JT  - Clinical endocrinology
JID - 0346653
RN  - 0 (Gastrins)
RN  - 0 (Multienzyme Complexes)
RN  - 789U1901C5 (Copper)
RN  - EC 1.- (Mixed Function Oxygenases)
RN  - EC 1.14.17.3 (peptidylglycine monooxygenase)
RN  - PQ6CK8PD0R (Ascorbic Acid)
SB  - IM
MH  - Anemia, Pernicious/blood
MH  - Ascorbic Acid/metabolism
MH  - Copper/metabolism
MH  - Eating/physiology
MH  - Enzyme Activation/physiology
MH  - Freezing
MH  - Gastrins/blood/*metabolism
MH  - Humans
MH  - Mixed Function Oxygenases/*blood/metabolism
MH  - *Multienzyme Complexes
MH  - Multiple Endocrine Neoplasia/blood
MH  - Vitamin B 12 Deficiency/blood
EDAT- 1993/07/01 00:00
MHDA- 1993/07/01 00:01
CRDT- 1993/07/01 00:00
PHST- 1993/07/01 00:00 [pubmed]
PHST- 1993/07/01 00:01 [medline]
PHST- 1993/07/01 00:00 [entrez]
AID - 10.1111/j.1365-2265.1993.tb01750.x [doi]
PST - ppublish
SO  - Clin Endocrinol (Oxf). 1993 Jul;39(1):51-8. doi: 
      10.1111/j.1365-2265.1993.tb01750.x.