Altered post-receptorial signal transduction mechanism under various stimulation in polymorphonuclear granulocytes of Alzheimer's disease.
The cyclic nucleotide changes were studied under 10(-6) M isoproterenol (IP), 10(-6) M carbachol and 10(-8) M Met-enkephalin (Met-enk) stimulations in polymorphonuclear granulocytes (PMNLs) of middle-aged (aged 35-52 years) and elderly (aged 61-97 years) healthy subjects, as well as of patients with Alzheimer's disease (AD) (aged 58-65 years). From our results we can conclude that in the case of middle-aged healthy subjects only the IP caused a marked cAMP elevation while in elderly and AD all the applied substances stimulated the cAMP at different degrees. Concerning the cGMP levels in PMNLs, we observed a marked increase under carbachol and Met-enk stimulation, in middle-aged subjects, while in the elderly a weak change was obtained by carbachol. In AD practically no change of cGMP levels could be obtained. Thus, the main features of AD are a cAarP response to Met-enk and an abolition of a GarP response to carbachol. We can conclude that in PMNLs of elderly and patients with AD we assist to an altered post-receptorial signal transduction mechanism, which seems to be even more marked in the case of AD comparing to normal aging.
Fulop
T
T
First Department of Medicine, University Medical School of Debrecen, Hungary.
Kekessy
D
D
Foris
G
G
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000544:Alzheimer Disease / Q000276:immunology*; D002217:Carbachol / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism / Q000502:physiology*; D006152:Cyclic GMP / Q000378:metabolism / Q000502:physiology*; D004744:Enkephalin, Methionine / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology*; D015398:Signal Transduction
D004744:Enkephalin, Methionine; D002217:Carbachol; D000242:Cyclic AMP; D006152:Cyclic GMP