These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Patterns of cyclic nucleotides in normal and leukaemic human leucocytes. Author: Peracchi M, Maiolo AT, Lombardi L, Catena FB, Polli EE. Journal: Br J Cancer; 1980 Mar; 41(3):360-71. PubMed ID: 6104501. Abstract: Because recent observations indicate that metabolism of cyclic nucleotides may be altered in neoplastic cells, the intracellular levels of cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP) were measured in mononuclear leukaemic and normal human leucocytes. The activities of adenylate cyclase, guanylate cyclase and cyclic nucleotide phosphodiesterases were also determined. Under basal conditions, cAMP levels were always higher in the normal leucocytes, whilst cGMP levels were of the same order of magnitude in both normal and leukaemic cells, causing the cAMP/cGMP ratios to be significantly lower in leukaemic leucocytes. Leukaemic cells significantly increased cyclic nucleotide levels in response to theophylline, but did not respond to serotonin, carbamylcholine or D,L-isoproterenol. Preincubation of these leucocytes with theophylline produced a detectable cAMP response to D,L-isoproterenol but no cGMP response to serotonin or carbamylcholine was found. Adenylate cyclase and guanylate cyclase were significantly lower in leukaemic than in normal cells, which could largely explain the abnormal cyclic nucleotide pattern found in human leukaemic leucocytes. In our experiments, cAMP phosphodiesterase activity was comparable in normal and leukaemic cells, whereas cGMP phosphodiesterase activity was undetectable inall mononuclear-leucocyte preparations with the methods used.[Abstract] [Full Text] [Related] [New Search]