T. Petteri Piepponen, Ph.D.
Docent in Pharmacology
Senior lecturer
Division of Pharmacology and Toxicology
Faculty of Pharmacy
POB 56
00014 University of Helsinki
Finland
email petteri.piepponen-at-helsinki.fi
Tel. +358-9-191 59477, fax +358-9-191 59471
Research interests: GDNF family neurotrophic factors, dopamine, Parkinson's disease, addiction
Dopamine is a unique neurotransmitter in the CNS as it controls both motor functions and motivated behaviour. Thus, perturbations in cerebral dopaminergic transmission are directly linked to pathological conditions such as Parkinson's disease (PD) and addiction. Glial Cell-Line Derived neurotrophic factor (GDNF) is an important regulator of dopaminergic neurons and it exhibits survival-promoting effects on midbrain dopamine neurons in vitro and in rodent models of PD in vivo. Our goal is to elucidate the mechanisms of action of GDNF in these effects and characterize in detail the molecular and functional changes occurring in the dopaminergic transmission induced by increased or decreased GDNF signaling.
Main research methods: Microdialysis (dopamine, GABA), stereotaxic lesion models, dopamine tissue estimations, stereological cell countings, immunohistological stainings, locomotor activity, conditioned place preference, turning behaviour.
Recent publications:
Airavaara M, Tuomainen H, Piepponen TP, Saarma M, Ahtee L: Effects of repeatedly administered morphine on locomotor activity, conditioned place preference and extracellular dopamine in heterozygous GDNF knockout mice. Genes, brain, and behavior, 6, 287-98, 2007.
Rantamäki T, Hendolin P, Kankaanpää A, Mijatovic J, Piepponen TP, Domenici E, Chao MV, Männistö PT, Castrén E: Pharmacologically diverse antidepressants rapidly activate brain- derived neurotrophic factor (BDNF) receptor TRKB and induce phopholipase-Cγ signaling pathways in mouse brain. Neuropsychopharmacology, 32:2152-62, 2007.
Mijatovic J, Airavaara M, Planken A, Auvinen P, Raasmaja A, Piepponen TP, Costantini F, Ahtee L, Saarma M: Constitutive Ret activity in knock-in MEN2B mice induces profound elevation of brain dopamine concentration via enhanced synthesis and increases number of TH-positive cells in substantia nigra. Journal of Neuroscience, 27:4799-809, 2007.
Marttila K, Piepponen TP, Kiianmaa K, Ahtee L: Accumbal FosB/DeltaFosB immunoreactivity and conditioned place preference in alcohol-preferring AA rats and alcohol-avoiding ANA rats treated repeatedly with cocaine. Brain Research. 1160:82-90, 2007.
Mijatovic J, Patrikainen O, Yavich L, Airavaara M, Ahtee L, Saarma M, Piepponen TP: Characterization of the striatal dopaminergic neurotransmission in MEN2B mice with elevated cerebral tissue dopamine. Journal of Neurochemistry, 105, 1716-1725, 2008.
Vihavainen T, Relander TRA, Leiviskä R, Airavaara M, Tuominen RK, Ahtee L, Piepponen TP: Chronic nicotine modifies the effects of morphine on extracellular striatal dopamine and ventral tegmental GABA. Journal of Neurochemistry, 107, 844-54, 2008.
Uutela P, Karhu L, Piepponen TP, Käenmäki M, Ketola RA, Kostiainen R: Discovery of dopamine glucuronide in rat and mouse brain microdialysis samples using liquid chromatography tandem mass spectrometry. Analytical Chemistry 81, 427-434, 2009.
Palgi M, Lindström R, Peränen J, Piepponen TP, Saarma M, Heino TI: Drosophila MANF - the first invertebrate homologue to mammalian neurotrophic factors supports dopaminergic neurons. PNAS 106:2429-2434, 2009
Uutela P, Ketola RA, Piepponen TP, Kostiainen R: Comparison of different amino acid derivatives and analysis of rat brain microdialysates by liquid chromatography tandem mass spectrometry. Analytica Chimica Acta, 633, 223-231, 2009.
Kaste K, Kivinummi T, Piepponen TP, Kiianmaa K, Ahtee, L: Differences in basal and morphine-induced FosB/deltaFosB and pCREB immunoreactivities in dopaminergic brain regions of alcohol-preferring AA and alcohol-avoiding ANA rats. Pharmacology, Biochemistry & Behavior, 92, 655-662, 2009.
Mijatovic J, Piltonen M, Alberton P, Männistö PT, Saarma M, Piepponen TP: Constitutive Ret signaling is protective for dopaminergic cell bodies but not for axonal terminals. Neurobiology of Aging, in press.
Uutela P, Reinilä R, Harju K, Piepponen TP, Ketola RA, Kostiainen R: Analysis of intact glucuronides and sulfates of serotonin, dopamine, and their phase I metabolites in rat brain microdialysates by liquid chromatography-tandem mass spectrometry. Analytical Chemistry 81, 8417-8425, 2009.
Kallonen SE, Tammimäki A, Piepponen TP, Raattamaa H, Ketola RA, Kostiainen R: Discovery of neurosteroid glucuronides in mouse brain. Analytica Chimica Acta, in press.
Jäntti SE, Tammimäki A, Raattamaa H, Piepponen TP, Kostiainen R, Ketola RA: Determination of steroids and their intact glucuronide conjugates in mouse brain by capillary Liquid Chromatography-tandem Mass Spectrometry. Analytical Chemistry, in press.
Segerstråle M, Kolehmainen J, Piepponen TP, Lauri SE, Mulle C, Taira T: High firing rate of neonatal hippocampal interneurons is due to attenuation of afterhyperpolarizing potassium currents by tonically active kainate receptors. Journal of Neuroscience, in press.