Effect of VIP on the respiratory burst in human monocytes ex vivo during prolonged strain and energy deficiency.
VIP-stimulated cyclic AMP production and VIP effect on the production of reactive oxygen compounds in human monocytes activated by serum opsonized zymosan (respiratory burst) were studied during a ranger training course lasting for five days with almost continuous physical activity, and deficiency of sleep and energy. Respiratory burst was inhibited and cyclic AMP production was stimulated by VIP on all days. Maximum cyclic AMP production stimulated by VIP (0.1 microM) on the day of control was 148.6% of basal, and 255.3%, 213.8%, 218.9% and 198.7% on Days 1, 2, 3 and 5. Maximum inhibition was observed 20 min after addition of the peptide on the day of control, after 5 min on Days 1, 2 and 3, and after 10 min on Day 5. Inhibition at the 5-min time point was 33.1% on the day of control, and 34.7%, 53.6%, 53.3% and 36.2% on the different days during the training course. The observed increment in VIP effect adds to prior reported data about increased VIP secretion during the training course, and may indicate enhanced physiological significance of VIP during stress.
Wiik
P
P
Norwegian Defence Research Establishment, Division for Environmental Toxicology, Kjeller.
Haugen
A H
AH
Løvhaug
D
D
Bøyum
A
A
Opstad
P K
PK
D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis; D004734:Energy Metabolism / Q000187:drug effects*; D015444:Exercise; D006801:Humans; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects*; D013552:Swine; D013997:Time Factors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP