Sex differences in the IntelliCage and the Morris water maze in the APP/PS1 mouse model of amyloidosis

Experiments

Items

Material	Material Usage	Supplier
IntelliCage	Automated system to engage animals in behavioral tasks using access to water as incentive	N/A
RFID chips	Identification of a mouse when it enters a corner of the IntelliCage system	DataMars, Switzerland & Troven, USA

Instructions

1
During the adaptation phase, all doors were open for free access to water. In later phases, correct and incorrect response paradigms were used to train the mice.
2
For place preference, water was available in one corner based on individual mouse habits. In the reversal phase, the reward corner was moved.
3
In the SRT tasks, a nosepoke is required when a green LED is illuminated within a specific time frame. The duration of illumination was varied to increase task difficulty.
4
For place avoidance, airpuff was administered upon entry into a specific corner, followed by a retention phase to test memory extinction.

Methodologies

The IntelliCage was used to assess water drinking behavior, spatial learning and reference memory, behavioral flexibility, attention, and contextual memory.
The testing apparatus contains 4 corner chambers accessible through an open tunnel equipped with an antenna. RFID chips are detected by a scanner and temperature sensor located at the entrance of each corner that registers when an animal enters.
Tasks: Adaptation phase, Place preference, Serial Reaction Time 1 and 2, Place Avoidance.

Items

Material	Material Usage	Supplier
Circular tank	Used for Morris water maze testing; 1.5 m in diameter, filled with water	N/A
Nontoxic white paint	Added to opaque the water and hide the platform	N/A

Instructions

1
Guide animals to the hidden platform if they fail to locate it in 60 seconds. Allow them 10 seconds on the platform to consolidate spatial cues.
2
Return animals to a resting cage with a heating pad between trials.
3
Analyze data using EthoVisionXT system, focusing on latency, platform crossings, and swim speed.

Methodologies

MWM testing involves a circular tank with a hidden platform submerged 1.5 cm beneath the water. The platform's location remains constant during the learning phase, while the entry point changes.
Animals undergo four 60-second trials per day for five days to locate the hidden platform using extramaze cues.
A probe trial without the platform is conducted 24 hours after the last learning trial to assess memory retention.