Stress en pijn in vissen

Transcription

Stress en pijn in vissen
Stress en pijn in vissen
Stress & Pain in fish
Gert Flik c.s.
Animal Physiology
IWWR
Radboud University Nijmegen
Stress is an old phenomenon
Cladogram extant chordates
450 Myear
Caroll 1988 and Butler 1994
Number of families
Mass extinctions
and diversity of marine species
800
600
400
200
Rate of extinction
(families per M year)
0
20
15
10
5
0
Cm
600
O
S D
C
P Tr J
200
400
Geological time scale (M year)
K
T
0
Phylogeny and ontogeny
Model species
Cyprinus carpio
Oreochromis mossambicus
Stress & Pain in fish
• Anatomy
• Physiology
• Behavior
Polymodal nociceptors
Mechanothermal receptors
Mechanochemical
receptors
Nociception in trout
Behavioral responses in trout after pain stimuli
FIN CLIPPING
1. C-fibers
2. A-fibers
3. Schwann cell
Dark/light preference of Nile tilapia
Gill chloride cells, control fish
Gill chloride cells, injured fish
Gill mucus cells
Stress, pain and brain in fish
Trout brain
Dorsal view
Lateral view
Development TELENCEPHALON in vertebrates
a. newts - mammals
b. & c. Modern teleosts
6: Hippocampal pallium
35.000 species of fish
35.000 kinds of brains...
Typical and specialised brains
A travel from nose to tail through
the central nervous system of fish,
with some excursions…
Goldfish bulbus olfactorius
Trout
Telencephalon
Cortex cerebri Tropheus: dendritic spines,
basics for cellular memories
Hypothalamus and preoptic area in catfish
Clarias gariepinnus
Dynamic interaction
with environment
• Sensor & signal system: brain and endocrine stress
axis, with hypothalamus as ‘nerve centre’
Stress response :
dynamic interaction with the environment
Hypothalamus
CRH
CRH
CRH
Pituitary gland
ACTH
-
ACTH
Interrenal cells
Cortisol
-
cortisol
-
Cold stress and HPI-axis in
vivo: fMRI
Magnet
RF-antenna
MS-222
15°C
Aquaria
Water leaving via
the gills
Intubation
25°C
MS-222
Parameters: Cerebral blood volume
Deoxyhaemoglobin content (BOLD-fMRI)
Plasma cortisol after cold shock
**
26
24
250
200
**
*
22
150
20
100
18
50
16
0
-30
-20
-10
0
10
20
30
40
Temperature (°C)
[cortisol] (ng/ml)
300
50
Time (min)
Van den Burg et al., Neuroendocrinology 77, 15-23, 2003
Changing blood volume
during temperature drop
Decrease in blood volume
during temperature drop
Increase in blood volume
during temperature drop
BOLD f MRI
Blood Oxygen Level Dependent
Functional Magnetic Resonance Imaging
Oxygenated and desoxygenated
hemoglobulin behave magnetically
differently,
the oxygenation degree makes the Hb a
contrast dye
CBV and BOLD signals in the
preoptic area (poa)
5 min
Signal change (%)
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
mt
poa
-10
-10
)
2
40
BOLD MRI corrected
2
0
-2
-4
-6
-8
-10
0
10
20
30
Time after onset of the temperature drop (min)
4
BOLD-fMRI
0
10
20
30
Time after onset of the temperature drop (min)
4
CBV MRI corrected
Signal change (%)
Signal change (%)
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-3.0
20
min
CBV
MRI corrected
BOLD MRI corrected
40
-10
0
10
20
30
Time after onset of the temperature drop (min)
40
BOLD-f MRI
Tuberal Hypothalamus
BOLD-f MRI: pituitary gland
p.d.
p.i.
Summary f MRI
CBV
NPO
TH
PD
Cortisol
0
1
2
3
4
Time (minutes)
5
15
20
25
30
Carp
NV, NVII, NVIII
Motor learning
Corpus cerebelli
Sensory modalities
Valvula cerebelli
Endorfins in fish
oCRF
A
B
NPO
ACTH 10-23
NPO
Pars
distalis
NF
PD
ON
Pars intermedia
PI
500µm
C
D
All Endorphins
N-acetylated Endorphin
Cerebellum
The palatal organ of carp
For those understanding the dutch
Het smaakzintuig van een karper Het smaakzintuig
bevindt zich in het smaakorgaan van de karper. Bij
karpers is de mond het belangrijkste smaakorgaan. De
voornaamste smaakpupillen, of het palatale orgaan,
zitten in het gehemelte, maar ook op de lippen, de
baarddraden, het kieuwenorgaan en bij de borstvinnen
zitten bepaalde soorten smaakpapillen. Het
smaakorgaan is gevoelig voor zuur, zoet, zout en
kruiden, en het is ongelooflijk gevoelig in vergelijking met
die van ons als mens.
Bron: BBKBiesboschkarpers.nl
The palatal organ of carp
Carp have a highly specialised structure
in their mouth, situated in the dorsal
palate, with which they analyse food
sucked in for potential nice food.
Extremely delicate organ with large
representation in cerebellar vagal lobe.
Vagal lobe: connections in cyprinids
Cypriniden: vagal lobe
connectivity and organisation
Cerebellum
electric fish
Projections to medulla oblongata and
spinal cord
Eel
Goldfish
Pallial areas in fish: analogues of
learning centres and basis for
awarenes/sentience as seen in
mammals?
Ictalurus punctatus: projections
‘up’ and processing in telencephalon
Afferent, efferent and intrinsic connections in
telencephalon of teleosts
Evolution of nociception in
vertebrates: comparative analysis of
lower vertebrates.
Sneddon LU.
Sneddon and Vanderlinden (Glasgow, SEB): activation of
telencephalon during pain demonstrated by MRI
Do we need a neencephalon to remember, to
experience pain,or to be aware of what’s going on
?
There is enough complexity in fish lateral
pallium to suspect sentience in fish
Goldfish remember pain way longer
than 3 seconds…
Jonathan Nilsson et al.
• Atlantic cod can associate two timeseparated events (trace conditioning) and
has long time (>88days) retention of
learned associations
• There is awareness-dependent declarative
representation of future events!

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