Cyclic AMP-binding capacities and histone kinase activation in subcellular components of neocortical tissue. Differential responses to three neurohumoural agents |
| |
Authors: | Jitendra Patel Michael Newman and Henry McIlwain |
| |
Institution: | Department of Biochemistry, Institute of Psychiatry (British Postgraduate Medical Federation, University of London), De Crespigny Park, London SE5 8AF, U.K. |
| |
Abstract: | 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. |
| |
Keywords: | |
|
|