Cyclic AMP-binding capacities and histone kinase activation in subcellular components of neocortical tissue. Differential responses to three neurohumoural agents.
1. Noradrenaline and histamine, when added to superfused guinea-pig cerebral-cortical tissues, increased both cyclic AMP-dependent and -independent histone kinase activities of some, but not of all, subsequently isolated subcellular fractions, and decreased their cyclic [(3)H]AMP-binding capacity, which was concluded to be due to an increase in endogenously bound cyclic AMP. 2. Adenosine and 2-chloroadenosine also diminished the cyclic [(3)H]AMP-binding capacities, but did not affect the histone kinase activities. 3. DEAE-cellulose chromatography and stability to KCl additions showed that the greater part of the histone kinase of the present preparations corresponded to the type II enzyme [of Corbin, Keely & Park (1975) J. Biol. Chem.250, 218-225], with a lesser amount of type I activity. Different sites of cyclic AMP accumulation in relation to these or other kinases are considered in interpreting the differential tissue responses to the neurohumoural agents examined.
D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D002848:Chromatography, DEAE-Cellulose; D000242:Cyclic AMP / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D009638:Norepinephrine / Q000494:pharmacology; D006656:Protamine Kinase / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism
D018377:Neurotransmitter Agents; D006632:Histamine; D000242:Cyclic AMP; D011494:Protein Kinases; D006656:Protamine Kinase; D000241:Adenosine; D009638:Norepinephrine