PMID- 2168410
OWN - NLM
STAT- MEDLINE
DCOM- 19901011
LR  - 20210210
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 265
IP  - 26
DP  - 1990 Sep 15
TI  - Vasoactive intestinal peptide, a singlet oxygen quencher.
PG  - 15371-4
AB  - The neuropeptide vasoactive intestinal peptide (VIP), a highly basic 28-amino 
      acid peptide, has a widespread distribution in the body. The functional 
      specificity of this peptide not only includes its potent vasodilatory activity, 
      but also its role in protecting lungs against acute injury, in preventing 
      T-lymphocyte proliferation and in modulating immune function. We have 
      investigated the possible antioxidant properties of VIP and found that VIP does 
      not have significant O2-, OH., or H2O2 scavenging ability. However, VIP was found 
      to inhibit, in a dose-dependent manner, the 1O2-dependent 
      2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) formation. 1O2 was produced in 
      photosensitizing systems using rose bengal or methylene blue as sensitizers and 
      was detected as TEMP-1O2 product (TEMPO) by electron paramagnetic resonance (EPR) 
      spectroscopic techniques. The formation of TEMPO signal was strongly inhibited by 
      known singlet quenchers, e.g. beta-carotene, histidine as well as azide, but not 
      by catalase (20 micrograms/ml) which removes H2O2 and mannitol (6 mM) or ethanol 
      (5.9 mM) which remove OH.. Superoxide dismutase (2.5 micrograms/ml) inhibited the 
      photoreaction up to 20% by removing O2- and most probably by blocking the 
      secondary charge transfer pathway of 1O2 formation. These results suggest that 
      the formation of nitroxide radical by 1O2 attack on TEMP may be used as a simple 
      and specific assay for 1O2, and VIP can serve as an effective 1O2 
      scavenger/quencher, thus it may modulate the oxidative tissue injury caused by 
      this reactive species of oxygen.
FAU - Misra, B R
AU  - Misra BR
AD  - Department of Biomedical Sciences, College of Veterinary Medicine, Virginia 
      Polytechnic Institute, Blacksburg 24061.
FAU - Misra, H P
AU  - Misra HP
LA  - eng
GR  - HL-42009/HL/NHLBI NIH HHS/United States
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Cyclic N-Oxides)
RN  - 1393-25-5 (Secretin)
RN  - 17778-80-2 (Singlet Oxygen)
RN  - 37221-79-7 (Vasoactive Intestinal Peptide)
RN  - S88TT14065 (Oxygen)
RN  - VQN7359ICQ (TEMPO)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Cyclic N-Oxides
MH  - Electron Spin Resonance Spectroscopy/methods
MH  - Kinetics
MH  - Molecular Sequence Data
MH  - *Oxygen
MH  - Photolysis
MH  - Secretin/genetics
MH  - Sequence Homology, Nucleic Acid
MH  - Singlet Oxygen
MH  - Swine
MH  - Vasoactive Intestinal Peptide/genetics/*metabolism
EDAT- 1990/09/15 00:00
MHDA- 1990/09/15 00:01
CRDT- 1990/09/15 00:00
PHST- 1990/09/15 00:00 [pubmed]
PHST- 1990/09/15 00:01 [medline]
PHST- 1990/09/15 00:00 [entrez]
AID - S0021-9258(18)55404-1 [pii]
PST - ppublish
SO  - J Biol Chem. 1990 Sep 15;265(26):15371-4.