FP6 priority

1.1.1   Genomics and Biotechnology for Health

1.1.1.1

Title of the proposal

GENOMIC PROCESSES INVOLVED IN REGULATION OF CATECHOLAMINERGIC SYSTEMS DURING STRESS

Institute

Slovak Academy of Sciences, Institute of Experimental Endocrinology (Centre of Excellence EU)
Vlarska 3, 833 06 Bratislava, Slovak Republic

Contact

Research subject for a potential FP6 project

Research subject is oriented on genomic processes in catecholaminergic systems and their modulation by stress stimuli. Basis of the project is to explain mechanisms by which the biosynthesis of catecholamines (CA) is regulated in vivo in the adrenal medulla, sympathetic ganglia, heart, spleen and various areas of the brain. We focused mainly on enzymes, involved in the biosynthesis of catecholamines – tyrosine hydroxylase, dopamin-b-hydroxylase (DBH) and phenylethanolamine-N-methyltransferase (PNMT). Since the first possible target of the modulation of these enzymes is their gene expression, we used various RT-PCR approaches (semi-quantitative, seminested, quantitative competitive, real-time) to evaluate changes in the mRNA levels of these enzymes. Transcriptional mechanisms and transcriptional factorss essential for gene expression of CA enzymes were studied as well. We also measured protein levels by Western blot analysis and the activity of CA enzymes. In order to study the mechanisms of modulation of in vivo CA production, we have used several models of transgenic animals (DBH-knock-out, cfos-knock-out, corticoliberin-knock-out). We described PNMT gene expression (the enzyme responsible for adrenaline formation) in four parts of the heart, spleen and thymus and found glucocorticoid-dependent changes in PNMT mRNA levels under stress.
Gene expression of the enzymes was also studied in various hypothalamic and brain stem nuclei in rats exposed to a single or repeated stress stimuli. Both, in situ hybridization and quantitative competitive RT-PCR techniques were used. Effect of various brain nuclei (paraventricular and dorsomedial nuclei, A5, A11 areas, etc.) on activity of peripheral sympa-thoadrenal system (SAS) has been studied in rats with lesion or deafferentation. Effect of weightlessness during space flight of humans or animals on SAS activity has also been studied.

Recent international cooperation of the research team

National Institute of Mental Health and National Institute of Neurological Disorders and Stroke NIH, Bethesda, MD, USA; New York Medical College, Valhalla, NY, USA; Rutgers University, Piscataway, NJ, USA; Harvard Medical School, Belmont, MA, USA, Institute of Biomedical Problems, Moscow, Russia; Semmelweis University, Budapest, Hungary

Proposer´s relevant publications related to the research subject

Sabban E.L. and Kvetnansky R.: Stress-triggered activation of gene expression in catecholaminergic systems: Dynamics of transcriptional events.
TREND in Neurosciences 24, 91-98, 2001.
Krizanova O., Micutkova L., Jelokova J., Filipenko M., Sabban E., Kvetnansky R.: Existence of cardiac PNMT mRNA in adult rats: Elevation by stress in a glucocorticoid-dependent manner. Am. J. Physiol., Heart. Circ. Physiol. 281, H1372-H1379, 2001.
Rusnak M., Kvetnansky R., Jelokova J., Palkovits M.: Effect of novel stressors on gene expression of tyrosine hydroxylase and monoamine transporters in brainstem noradrenergic neurons of long-term repeatedly immobilized rats. Brain Research 899, 20-35, 2001.