METODI SPERIMENTALI PER LO STUDIO DEL COMPORTAMENTO. Farmacologia Speciale A.A

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1 METODI SPERIMENTALI PER LO STUDIO DEL COMPORTAMENTO Farmacologia Speciale

2 SPERIMENTAZIONE ANIMALE

biologiche che fanno dei primi dei buoni modelli per capire quel che accade

3 SPERIMENTAZIONE ANIMALE Utilizzo scientifico a scopo di studio e ricerca di animali Animali ed essere umano condividono geni, meccanismi e funzioni biologiche che fanno dei primi dei buoni modelli per capire quel che accade anche nella nostra specie, consentendo di fare deduzioni e predizioni RATTO TOPO

4 PRINCIPIO DELLE 3 R 1959 Reduction Replacement Refinement Riduzione Sostituzione Affinamento Incoraggia alternative alla sperimentazione animale Mira a migliorare il benessere degli animali e la qualità scientifica dove l uso di animali non può essere evitato

5 NEUROSCIENZE COMPORTAMENTALI Locomotor behavior Socio-Sexual interaction Emotional reactivity Learning and memory abilities Models of depression Motor coordination and balance

6 1) LOCOMOTOR BEHAVIOR Open-field: it consists of a square or circular platform where a rat or a mouse is released for exploration. An observer will record the number of square limit crossings with both forepaws; number of fecal boli; thigmotaxis (time spent near the walls); frequency and duration of rearing (standing with the body inclined vertically, forequarters raised), wall-rearing (standing on the hind-limbs and touching the walls of the apparatus with the forelimbs), grooming (rubbing the body with paws or mouth and rubbing the head with paws) and immobility. Di Giovanni et al. Brain Res, 1993; Candland and Nagy. Ann NY Acad Sci, 1969

1) LOCOMOTOR BEHAVIOR The open-field is useful for detecting any defect on spontaneous locomotor activity due to drug treatment, lesion in the brain, strain differences or genetic manipulation.

7 1) LOCOMOTOR BEHAVIOR The open-field is useful for detecting any defect on spontaneous locomotor activity due to drug treatment, lesion in the brain, strain differences or genetic manipulation. The open-field can also be used for testing anxiety in animals. The measure of latency and the patterns of exploration of the field are examined. Anxious animal will take longer time to adventure in the centre part of the arena. Another way of measuring anxiety is to introduce a novel object in the open-field and measure the time it takes for an animal to approach the novel object. This task is valuable in early phases of genetic phenotyping or drug screening.

10 2) SOCIO-SEXUAL INTERACTION Maternal behavior Sexual patterns Adult aggressiveness

11 MATERNAL BEHAVIOR Maternal care in rats and mice: Licking Nursing positions Nest building Retrieving Chantrey and Jenkins. Anim Behav, 1982; Noirot. Anim Behav, 1982; Laviola et al. Psychoparmacology, 1990 No Maternal Behavior Passive Nursing Arched Nursing

12 SOCIAL INTERACTION AND ADULT AGGRESSIVENESS

13 SOCIAL INTERACTION AND ADULT AGGRESSIVENESS

14 SOCIAL INTERACTION AND ADULT AGGRESSIVENESS sostanze dopanti (steroidi androgeni anabolizzanti) psicostimolanti (cocaina ed amfetaminici)

15 3) EMOTIONAL REACTIVITY Ultrasonic vocalization test Elevated zero or plus-maze test Social interaction test

16 ULTRASONIC VOCALIZATION TEST The ultrasonic vocalization test, performed recording ultrasonic calls emitted by pups removed from their nest, is considered a reliable tool to investigate the anxiolytic and anxiogenic activity of drugs. One male per litter for each treatment will be randomly removed from the nest and, after axillary s temperature measure, placed in a shallow glass dish (15 cm diameter and 10 cm deep) 15 sec before the test. This will confine the pup relative to the microphone, which will be supported vertically 15 cm above the dish and thus will avoid handling it during the recording session. Ultrasonic calls will be recorded for 15 sec to collect the baseline levels, then each pup will be injected with the drug or its vehicle, and returned to the nest. 30 min after the injection, ultrasonic emission will be recorded for 15 sec. The number of calls will be counted by listening to the audible output of the bat-detector. Data will be expressed as percent change from baseline. Gardner. J Pharmacol Methods, 1985; Insel et al. Pharmacol Biochem Behav, 1986

18 Flat call Frequency steps call 3-Syl call 2-Syl call

19 Effects of Diazepam

ELEVATED ZERO OR PLUS- MAZE TEST Zero-maze test: this test, based on the natural aversion and avoidance of rodents for open spaces, is a modification of the elevated plus-maze model of anxiety which

20 ELEVATED ZERO OR PLUS- MAZE TEST Zero-maze test: this test, based on the natural aversion and avoidance of rodents for open spaces, is a modification of the elevated plus-maze model of anxiety which incorporates both traditional (% of time in the open arms) and novel ethological measures (number of head dipping over the edge and stretched-attend postures from the closed to the open quadrant). The design comprises an elevated annular platform with two opposite enclosed quadrants and two open, removing any ambiguity in interpretation of time spent on the central square of the traditional design and allowing uninterrupted exploration. Shepherd et al. Psychopharmacology, 1994; Bickerdike et al., Eur. Journal Pharmacology, 1994

21 ELEVATED ZERO-MAZE TEST Zero-maze test. Adult rats will be weighed and injected with the drug or its vehicle. 30 min after the injection rats will be individually placed on a closed quadrant and a 5-min test period will be recorded on videotape for subsequent analysis. Behavioural measures will be calculated as follows: (a) % time spent on the open quadrants (% TO); (b) number of exploratory head dips (HDIPS) made over the edge of the platform, either from the exit of the closed quadrant, or whilst on the open quadrant; (c) number of stretched-attend postures (SAP) made from the exit of a closed quadrant towards an open quadrant. This exploratory posture can be described as a forward elongation of the body, with static hind-quarters, followed by a retraction to the original position.

22 ELEVATED PLUS-MAZE TEST

24 Effetto delle benzodiazepine nell elevated plus-maze test

SOCIAL INTERACTION TEST The social interaction test was developed in the 1978 as the

anxiety, and to use a natural form of behaviour as the dependent measure.

interaction. This time decreases when rats/mice are anxious.

25 SOCIAL INTERACTION TEST The social interaction test was developed in the 1978 as the first animal test of anxiety that endeavoured to use ethologically relevant sources of anxiety, and to use a natural form of behaviour as the dependent measure. The dependent measure is the time that pairs of male rats or mice spend in social interaction. This time decreases when rats/mice are anxious. This test can be performed at different rat/mouse ages and with different conditions such as familiar or unfamiliar partner and arena.

26 SOCIAL INTERACTION TEST Adolescent male rats will be individually housed for 24 hours before the test; then they will be weighed and injected with drug or its vehicle. 30 min after the injection each rat will be tested in a 30 min period of social interactions with a same sex, age and strain unfamiliar partner. The unfamiliar pair will be placed in a cage identical to the home-cage with new sawdust as bedding. The behaviour of each pair will be video-recorded and scored. Scored social behaviours will be: Play behaviour (Wrestling, Pinning); Affiliative behaviours (Social inactive, Social rest, Allogrooming); Soliciting behaviours (Push, Crawl); Investigative behaviours (Follow; Mutual circle and Social sniffing). Non-social behaviours will be: Inactive, Exploring, Jumping, Digging and Selfgrooming. File and Hyde. Br J Pharmacol, 1978; File and Seth. Eur J Pharmacol, 2003

27 Social Play

28 4) LEARNING AND MEMORY ABILITIES

29 4) LEARNING AND MEMORY ABILITIES Object recognition task. Object recognition, which is assessed from the preference normal rodents display for investigating novel rather than familiar complex objects can be used to provide a valid and relatively pure measure of "working memory. Indeed, advantages associated with this class of measure include the fact that performance does not depend on the retention of a rule, nor is influenced by changes in responsivity to reward. Ennaceur and Delacour. Behav. Brain Res, 1988; Ennaceur et al. Exp. Brain Res., 1997; Bartolini et al. Pharmacol. Biochem. Behav., 1996

The MWM is a relatively simple procedure typically consisting of six day trials, the main advantage being the differentiation between the spatial (hidden-platform) and non-spatial (visible

31 SPATIAL MEMORY: MORRIS WATER MAZE The Morris Water Maze (MWM) was first established by neuroscientist Richard G. Morris in 1981 in order to test hippocampal-dependent learning, including acquisition of spatial memory and long-term spatial memory. The MWM is a relatively simple procedure typically consisting of six day trials, the main advantage being the differentiation between the spatial (hidden-platform) and non-spatial (visible platform) conditions. In addition, the MWM testing environment reduces odor trail interference. This has led the task to be used extensively in the study of the neurobiology and neuropharmacology of spatial learning and memory. The MWM plays an important role in the validation of rodent models for neurocognitive disorders such as Alzheimer's Disease.

32 SPATIAL MEMORY: MORRIS WATER MAZE

33 5) MODELS OF DEPRESSION: FORCED SWIMMING TEST In the forced swimming test, a rodent is placed in a cylindrical box containing cold (22-24 C) water. Antidepressants reduce floating and increase swimming and struggling. These parameters are considered to be an indicator of antidepressant activity. Porsolt. Nature, 1977

6) MOTOR COORDINATION AND BALANCE The Rotarod technique has proved to be of great value in research involving screening of drugs which are potentially active on balance and motor coordination.

In the beam walking test rodents are trained to traverse a series of elevated, narrow beams to reach an enclosed platform. The protocol measures foot slips and latency to traverse the beams.

34 6) MOTOR COORDINATION AND BALANCE The Rotarod technique has proved to be of great value in research involving screening of drugs which are potentially active on balance and motor coordination. It is used to asses the ability of an animal to balance on a rotating rod. Dunham et al. J Am Pharamc Assoc Sci Ed, 1957; Carter et al. J Neurosci, In the beam walking test rodents are trained to traverse a series of elevated, narrow beams to reach an enclosed platform. The protocol measures foot slips and latency to traverse the beams. Gentile et al. Behav Biol, 1999 A number of different parameters of gait can be analyzed simply and effectively using footprint patterns. To obtain footprints, a rodent s paws are coated with paints and the rodent is allowed to walk along a narrow, paper-covered corridor, leaving a track of footprints. Golani. Brain Resl, 1979

Rotarod Raised beam test These tests are most frequently used in

model of Parkinson s disease. Footprint analysis.

of footprints as they walk or run along a corridor to a goal box.

35 Rotarod Raised beam test These tests are most frequently used in conjunction with unilateral 6-hydroxydopamine (6- OHDA) lesions as a model of Parkinson s disease. Footprint analysis. The paws are dipped in ink or paint, so that the animals leave a trail of footprints as they walk or run along a corridor to a goal box. Measurements of stride length, base width, and fore and hind paw overlap give an indication of gait.

36 Mouse behavioral assays for the major symptom categories of schizophrenia. Positive symptoms. The psychomotor agitation and hyperresponsivity to psychotomimetic drugs found in schizophrenia can be modeled in mice by testing locomotor responses in novel and stressful environments (A) and locomotor hyperactivity-inducing effects of psychotomimetics, such as NMDAR antagonists (B), respectively. Negative symptoms. Schizophrenia is often associated with blunted affect, social withdrawal, and loss of pleasure in normally rewarding activities (anhedonia). Social interactions with other mice (C) and decreased preference or motivation to obtain rewarding substances, such as sucrose (D), can be assessed as a means to model these negative symptoms. Cognitive/executive symptoms. Abnormalities in cognition and executive functions are a prominent feature of schizophrenia and range from deficits in episodic memory, poor attention and sensorimotor gating, to impaired reversal learning and set-shifting. Learning and memory can be tested in mice using, e.g., the reference memory version of the Morris water maze (E), while prepulse inhibition of the startle response provides a ready measure of sensorimotor gating (F).

Assessing mouse behaviors: Modeling pediatric traumatic brain injury

Assessing mouse behaviors: Modeling pediatric traumatic brain injury Bridgette Semple Ph.D. Postdoctoral Fellow, Noble Laboratory Department of Neurological Surgery, UCSF Pediatric Traumatic Brain Injury