We assessed physiological parameters in 4, 12, 20 and 28 month old C57BL/6 and CB6F1 male mice using a rotating rod, a free running wheel, and a photo beam activity field, designed to determine changes in coordinated walking ability, self-motivated running distance, and anxiety response to a novel environment, respectively.
The Truscan Photo Beam Activity System (Coulbourn Instruments, Whitehall, PA) was used, which consists of an arena (25.4 cm square) and a nose poke floor with 16 holes (4×4 array) with sensor rings to track movement.
Plasma wave activity detected by the Radio and Plasma Wave instrument suggests electron beam activity.
Locomotor activity: After completion of the reversal phase, locomotor activity was measured in all rats using 12 computerized photocell beam activity cages.
Rhythmic, but prolonged cross-beam activity was recorded in rye homozygotes.
A natural extension of the single beam hardware is the multi-beam activity monitor (MAM), also from Trikinetics, Inc. which manufactures the commonly used DAM.
Daily activity and energy expenditure were measured using Columbus Instruments small animal indirect calorimeters with Opto-M Varimex Minor activity monitors, which measure horizontal and ambulatory (non-consecutive beam breaks) activity using infrared beams, as previously described [16].
This is not an easy distinction to make based on any locomotor assay, but to gain some additional insight we introduced individual flies fed ad libitum into simple beam crossing activity monitors and measured their behavior until all flies had died from starvation.
Analysis of beam break activity divided into six 20-min time bins (ANOVA: Lesion Group3 × [Time Bin6 × S36]) revealed a main effect of time bin, F 5, 165) = 123; p <.0001, but no Lesion Group × Time Bin interaction, F(10, 165) = 1.5, p =.1.
Average velocity, ambulatory distance, vertical counts, vertical time, jump counts and jump time were measured over a 1-minute period and repeated five times for each mouse using a beam-breaker activity monitor (MEDOFA-510 activity chamber; Med Associates).
