Hormonal control of fructose 2,6-bisphosphate concentration in the HT29 human colon adenocarcinoma cell line. Alpha 2-adrenergic agonists counteract effect of vasoactive intestinal peptide.
Vasoactive intestinal peptide (VIP) was found to cause a dose-dependent decrease in fructose 2,6-bisphosphatase concomitant with an increase in cyclic AMP in cultured HT29 cancer cells from human colon. The maximum effect was a 41% decrease obtained with 10 nM-VIP, and half-maximum effect was obtained with 0.75 nM-VIP. The effect of 2.5 nM-VIP was almost totally counteracted (i.e. fructose 2,6-bisphosphate concentration was restored) by either adrenaline (1 microM) or the alpha 2-adrenergic agonist UK-14304 (1 microM); the alpha 2-agonist clonidine (1 microM) was less efficient, since the VIP effect was decreased by 72% only. The adrenaline effect was totally antagonized by 1 microM-yohimbine. It is concluded that, in the HT29 cancer cells, the fructose 2,6-bisphosphate-producing system is sensitive to variations of cyclic AMP concentration and is under the dual control of VIP and alpha 2-adrenergic receptors.
D000230:Adenocarcinoma / Q000378:metabolism*; D000068438:Brimonidine Tartrate; D002460:Cell Line; D003000:Clonidine / Q000494:pharmacology; D003110:Colonic Neoplasms / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D004837:Epinephrine / Q000494:pharmacology; D005635:Fructosediphosphates / Q000378:metabolism*; D006598:Hexosediphosphates / Q000378:metabolism*; D006801:Humans; D011810:Quinoxalines / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*; D015016:Yohimbine / Q000494:pharmacology
D005635:Fructosediphosphates; D006598:Hexosediphosphates; D011810:Quinoxalines; D015016:Yohimbine; D014660:Vasoactive Intestinal Peptide; D000068438:Brimonidine Tartrate; C027652:fructose 2,6-diphosphate; D000242:Cyclic AMP; D003000:Clonidine; D004837:Epinephrine