Curriculum vitae
et studiorum of Dr. Stefano Catarsi
Name Stefano
Catarsi
and birth-date
Present
address 3470 Simpson Street,
apt. 206, H3G 2J5 Montreal
Tel. 514-931-0498
e-mail: [email protected]
1980 Scientific high school diploma with
maximal marks (60/60).
1985 Bachelor degree in Biological Sciences
with
Maximal
marks (110/110 summa cum laude).
1987 Diploma of professional habilitation as
Biologist.
1991
Fellowship by the Italian National Center for Research to be spent
abroad.
1992 Ph.D. Diploma in
Neuroscience.
1993-94 Post-doctoral fellowship
by the International
Human
Frontier Organization.
1995-97 Post-doctoral fellowship
by the Medical
Research
Council of Canada.
1998-March
1999 Associate researcher at the
Montreal General Hospital, McGill University.
April
1999- Senior Research Scientist
at the Montreal Neurological Institute.
In 1983 he began to attend the
laboratories directed by Prof. Marcello Brunelli in the Department of
Physiology and Biochemistry of the University of Pisa (Italy) to accomplish his
bachelor thesis entitled: "Modulation of an electrical synapse in the
C.N.S. of Hirudo medicinalis". That thesis showed the reduction of
coupling between the two giant serotonergic neurons of the leech by serotonin
and dopamine through cAMP.
After his graduation, he spent a period
of one year recording from the CA1 field of the hippocampus as well as from Xenopus
oocytes expressing mammalian GABA channels.
He then carried out behavioral experiments using the
model of swim induction of the leech; it was found that the leech undergoes
simple forms of short- and long-term non-associative learning such as
habituation, dishabituation and sensitization. Serotonin
and octopamine, through cAMP, mimic short-term sensitization and dishabituation
while protein synthesis inhibitors block the long-term sensitization (Brunelli,
Catarsi & Traina, La serotonina:
impieghi clinici del precursore 5 idrossi-L-triptofano, 21-28, 1990; Brunelli
& Catarsi, Le molte facce della
memoria, 19-38, 1990; Brunelli, Catarsi,
Garcia, Scuri & Traina, Atti della Scuola di Neurobiologia della memoria,
1991). He also found that it is
possible to induce short-term dishabituation only in winter when the endogenous
serotonin is at its highest levels (Catarsi
et al. J. Comp. Physiol. A, 167:
469-474, 1990).
Afterwards, he performed experiments with
electrophysiological intracellular techniques, studying the modulation of the
after-hyperpolarization (AHP) following a discharge of the tactile sensitive T
neurons. He found that serotonin greatly reduces the AHP through the inhibition
of the Na+/K+ electrogenic pump (Catarsi & Brunelli, J.
exp. Biol. 155: 261-273, 1991). Also in this case serotonin was found to
act through cAMP (Catarsi et al. J. Physiol. (London) 462: 229-242,
1993). Later he has observed that
octopamine, through the serotonergic network, reduces the AHP in T neurons
while the intracellular electrical stimulation of the octopaminergic Leydig
neurons mimics this effect (Catarsi
et al. Neuroscience, 66/3: 751-759,
1995).
In 1991 he was awarded a fellowship by
the Italian National Center for Research that he spent in Prof. Pierre
Drapeau's Laboratories at the Research Institute for Neuroscience, McGill
University, Montreal. He carried out experiments on the pressure sensitive P
neurons of the leech in culture. By using patch-clamp in inside-out
configuration, he found that the cation channels of P cells lose PKC modulation
when the contact with the Retzius cells is restored (Catarsi & Drapeau, Neuron
8/2: 275-281, 1992).
On April 1992 he defended his Ph.D. thesis,
entitled: "Non-associative learning of swim induction in Hirudo
medicinalis: behavioral, electrophysiological, neuro-chemical and
neuro-anatomical analysis" and he obtained his Ph.D. in Neuroscience.
Afterwards he continued his studies in the Laboratories
of Prof. Drapeau as a post-doctoral Fellow funded by the International Human
Frontiers organization and later by a fellowship from the Medical Research
Council of Canada.
He took part
in a series of experiments performed at the level of P cells growth cones; it
was found that the loss of PKC modulation happens only within 20 mm from the zone
of contact of the two neurons. This phenomenon preludes to the formation of the
inhibitory synapses between the Retzius ad the P cell (Ching, Catarsi & Drapeau, J. Physiol. (London) 468: 425-439,
1993).
Later he used the patch-cramming
technique (Kramer, Neuron 2: 335-341, 1990), and discovered that tyrosine
kinase is involved in the molecular chain of events leading to the loss of
cation channel modulation of P neurons (Catarsi
& Drapeau, Nature: 363: 353-355,
1993). The cationic channels are tyrosine-phosphorylated at rest (Aniksztejn, Catarsi & Drapeau, J. Physiol. (London) 498: 35-142, 1997);
serotonin, through PKC, induces their dephosphorylation by activating a
tyrosine phosphatase (Catarsi &
Drapeau, J. Neurosci. 17: 5792-5797,
1997).
He has also studied the time course of
tyrosine kinase activity and its importance in synapse formation with
electrophysiological techniques as well as with antibody staining in single and
coupled P cells in culture (Catarsi ,
Ching, Merz & Drapeau, J. Physiol. (London)
485: 775-786, 1995) as well as the metabotropic and ionotropic activation of Cl-
synaptic channels (Ali, Catarsi and
Drapeau, J. Physiol. (London) 509:
211-219, 1998). The model suggested by
the experiments performed in these years of research in Prof. Drapeau's
Laboratories has been discussed in two review papers (Catarsi and Drapeau, Cellular
and molecular neurobiology, 16/6: 699-713, 1996; Drapeau, Catarsi and Merz, J. Phisiol. (Paris) 89: 115-123, 1995) and a paper describing the
methods has also been published (Drapeau, Catarsi
& Ali, Methods in Neuroscience,
1998).
In 1998 he has taken part to a new project
dealing with neuromuscular synapses in wild type and mutant zebra fish embryos
and larvae. He recorded muscle fiber miniature potentials in whole cell
configuration at different embryonic and larval stages. The results of these
developmental studies have been presented at the Neuroscience Meeting in
November 1998 and accepted for publication (Nguyen, Aniksztejn, Catarsi and Drapeau, J. Neurophysiol. 81 (6): 2852-2861,
1999).
On April 1999, he was offered a position of senior
scientist at the Montreal Neurological Institute where he is studying
expression, pharmacology and electrical properties of H+ activated
channels (ASICs) involved in pain sensation following inflammation and tissue
damage. In particular he has cloned two ASIC subunits and studied the molecular
and functional association of two subunits (2A and 3) in rat and human: these
subunits generate a heteromeric ionic channel with electrophysiological and
pharmacological properties different from those of the homomeric channels
(Babinski, Catarsi, Biagini and
Seguela, J. Biol. Chem., 275:
28519-28525, 2000).
More recently he has studied the modulation of ASICs
by endogenous neuro-peptides secreted during inflammation (Catarsi,
Babinski and Seguela, Neuropharmacology, 41: 592-600, 2001).
By using double-electrode voltage clamp on Xenopus
oocytes or whole cell recording of COS cells expressing ASIC channels combined
with Ca++ and Na+ imaging he is now studying their
possible interaction with other receptors as well as their sensitivity to potential
analgesic drugs. A behavioral and electrophisiological analysis of knockout
mice lacking an ASIC subunit has also been undertaken.
Dr. Catarsi has been teaching General Physiology,
Comparative Physiology, Electrophysiology and Neurobiology in the Department of
Physiology and Biochemistry of the University of Pisa (Italy) and he has been
part of the committee meeting for the students' evaluation.
Dr. Catarsi can write and speak fluently in English,
Italian and French and has also developed a large expertise in the computer
hardware and software used in biological research.