The effect of time of addition of glutamine or nucleosides on proliferation of rat cervical lymph-node T-lymphocytes after stimulation by concanavalin A.
1. Addition of concanavalin A to T-cell lymphocytes from rat cervical lymph nodes increases the activity of glutaminase within 1 h and those of carbamoyl-phosphate synthase II and aspartate transcarbamoylase within 3 h. There was a similar time course for the effects of concanavalin A on rates of glutamine utilization, which was increased within 1 h, and on pyrimidine nucleotide synthesis, which was increased by 40% at 2 h and by 100% at 3 h. 2. A delay in the addition of glutamine to the culture medium after addition of concanavalin A caused a decrease in [3H]thymidine incorporation only after 4-6 h. In the absence of glutamine, delay in addition of guanosine or inosine caused a decrease in [3H]thymidine incorporation only after 6-8 h after the addition of concanavalin A. 3. In contrast, a delay in addition of adenosine or uridine to the culture medium had an immediate effect (i.e. within 2 h) on the rate of incorporation of [3H]thymidine. It is suggested that adenosine and uridine have specific effects on proliferation via specific receptors for these nucleosides in the membrane.
Szondy
Z
Z
Department of Biochemistry, University of Oxford, U.K.
Newsholme
E A
EA
D000818:Animals; D002455:Cell Division; D003208:Concanavalin A / Q000494:pharmacology*; D005973:Glutamine / Q000378:metabolism*; D008198:Lymph Nodes / Q000166:cytology / Q000187:drug effects*; D009705:Nucleosides / Q000378:metabolism*; D011743:Pyrimidines / Q000096:biosynthesis; D051381:Rats; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D009705:Nucleosides; D011743:Pyrimidines; D005973:Glutamine; D003208:Concanavalin A