
Am J Psychiatry 159:66-73, January 2002
© 2002 American Psychiatric Association
[3H]cAMP Binding Sites and Protein Kinase A Activity in the Prefrontal Cortex of Suicide Victims
Yogesh Dwivedi, Ph.D.,
Robert R. Conley, M.D.,
Rosalinda C. Roberts, Ph.D.,
Carol A. Tamminga, M.D., and
Ghanshyam N. Pandey, Ph.D.
OBJECTIVE: The cAMP-dependent enzyme protein kinase A phosphorylates intracellular proteins upon activation and thereby plays a major role in mediating various physiological functions in the brain. To examine the role of this enzyme in suicidal behavior, the authors examined the catalytic and regulatory activities of protein kinase A in the postmortem brain of suicide victims. METHOD: Brain tissues were collected from 17 suicide victims and 17 nonpsychiatric comparison subjects. Regulatory activity was determined by examining [3H]cAMP binding to protein kinase A, while catalytic activity was determined by enzymatic assay in the presence (total activity) and the absence (endogenous activity) of cAMP in the membrane and cytosol fractions of the prefrontal cortex. RESULTS: The number (Bmax) of [3H]cAMP binding sites to protein kinase A was significantly lower in the suicide victims without any changes in affinity in either the membrane or cytosol fractions of the prefrontal cortex. Further, significantly less protein kinase A activity, both in the presence and the absence of cAMP, was seen in the membrane and cytosol fractions of the prefrontal cortex of suicide victims; however, the difference in total protein kinase A activity was much more pronounced. CONCLUSIONS: The results suggest that cAMP binding to the regulatory subunits of protein kinase A, as well as the phosphotransfer catalytic activity of protein kinase A, are lower in the prefrontal cortex of suicide victims than in nonpsychiatric comparison subjects, which may be of clinical relevance in the pathophysiology of suicidal behavior.
This article has been cited by other articles:

|
 |

|
 |
 
B. T. Hope, D. Nagarkar, S. Leonard, and R. A. Wise
Long-Term Upregulation of Protein Kinase A and Adenylate Cyclase Levels in Human Smokers
J. Neurosci.,
February 21, 2007;
27(8):
1964 - 1972.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Dwivedi, A. C. Mondal, H. S. Rizavi, G. Faludi, M. Palkovits, A. Sarosi, R. R. Conley, and G. N. Pandey
Differential and brain region-specific regulation of rap-1 and epac in depressed suicide victims.
Arch Gen Psychiatry,
June 1, 2006;
63(6):
639 - 648.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Z. Merali, L. Du, P. Hrdina, M. Palkovits, G. Faludi, M. O. Poulter, and H. Anisman
Dysregulation in the Suicide Brain: mRNA Expression of Corticotropin-Releasing Hormone Receptors and GABAA Receptor Subunits in Frontal Cortical Brain Region
J. Neurosci.,
February 11, 2004;
24(6):
1478 - 1485.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Dwivedi, H. S. Rizavi, R. R. Conley, R. C. Roberts, C. A. Tamminga, and G. N. Pandey
Altered Gene Expression of Brain-Derived Neurotrophic Factor and Receptor Tyrosine Kinase B in Postmortem Brain of Suicide Subjects
Arch Gen Psychiatry,
August 1, 2003;
60(8):
804 - 815.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Dwivedi, J. S. Rao, H. S. Rizavi, J. Kotowski, R. R. Conley, R. C. Roberts, C. A. Tamminga, and G. N. Pandey
Abnormal Expression and Functional Characteristics of Cyclic Adenosine Monophosphate Response Element Binding Protein in Postmortem Brain of Suicide Subjects
Arch Gen Psychiatry,
March 1, 2003;
60(3):
273 - 282.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Get information about faster international access.
a>
Privacy Policy
Copyright © 2002
American Psychiatric Association.
All rights reserved.
Home
| Search
| Current Issue
| Past Issues
| Subscribe
| All APPI Journals
| Help
| Contact Us
|