Behavioural activity of rats measured by a new method based on the piezo-electric principle

Abstract

Spontaneous and drug-induced (haloperidol, apomorphine, and amphetamine) motor activity of rats was measured simultaneously via two distinct and independent methods: the classical optical scanning technique and a new procedure based on the piezo-electric principle. The latter procedure measured animal-induced mechanical vibrations of a flexible cage floor which were transduced into electric signals via piezo-electricity. The piezo method appeared to be relatively more sensitive in recording the small, stereotyped motor movements induced by apomorphine (0.63- greater than or equal to 10 mg/kg) and high doses of amphetamine (2.5- greater than or equal to 20 mg/kg). The optical scanning technique, on the other hand, was more sensitive in recording horizontal displacements across the cage such as induced by low doses of amphetamine (0.31-2.5 mg/kg). Both methods showed comparable sensitivity in recording the depression of behaviour induced by haloperidol (0.04- greater than or equal to 1.25 mg/kg) or low doses of apomorphine (0.04-0.16 mg/kg). The piezo method may complement the optical scanning procedure, and thereby enhance the information on the extent that test compounds modify animal behaviour.

Mice lacking G0S2 are lean and cold-tolerant

“…Inner dimensions for the metabolic chamber were 10 × 10 × 8 cm and a motion sensor piezosensor 31 was embedded in gel in the base. After 2 h acclimation in the metabolic chamber, individual O 2 consumption and CO 2 production were recorded every 1 s by an O 2 analyzer S-3A/I (Applied Electrochemistry) and CO 2 analyzer CD-3A (Applied Electrochemistry), respectively.…”

Antipsychotic profile and side‐effect liability of haloperidol, risperidone, and ocaperidone as predicted from their differential interaction with amphetamine in rats

“…Locomotion and motility were measured simultaneously but independently in microprocessor-based motor activity meters [Megens et al, 1987[Megens et al, , 1989. Locomotion was defined as each change in number or location of interrupted infrared light beams (located in two arrays of 12 beams perpendicular to each other in a horizontal plane at 3 cm above the floor).…”

“…The pathology of schizophrenia can be mimicked in animals by amphetamine that activates the dopaminergic system indirectly by stimulating the release and inhibiting the re-uptake of biogenic amines, in particular dopamine [Cole, 1978;Fog et al, 1967;Iversen, 1977;Randrup and Munkvad, 19751. The behavioral effects of amphetamine in rats are dose-dependent [Megens et al, 1987[Megens et al, , 1989Randrup and Munkvad, 1975;Taylor and Snyder, 19711: low doses ( 5 5 mg/kg) produce hyperactivity (increased locomotion and rearing) and higher doses (>5 mg/kg) induce stereotyped behavior (unvaried, repetitive, and inappropriate sniffing, licking, and gnawing movements, the rats being withdrawn in a restricted area of the cage and apparently completely indifferent to their environment). The amphetamine-induced syndrome in rats is considered to be a valuable animal model of schizophrenia as it resembles this disease not only from a neurochemical but also from a behavioral point of view, the hyperactivity resembling the positive symptoms and the stereotypy the negative symptoms.…”

Differential effects of the new antipsychotic risperidone on large and small motor movements in rats: a comparison with haloperidol

“…Motor activity was measured in a new activity meter by optical scanning and by a new technique based on the piezo-electric principle (Megens et al 1987). The activity meter comprised five identical transparent test cages (23.3 x 23 x 30 cm).…”

“…In order to further delineate the behavioural profile and nature of action of risperidone, its effects on spontaneous motor activity in rats were investigated in comparison with those of the classical neuroleptic haloperidol. Motor activity was automatically recorded in a recently described activity meter (Megens et al 1987), which measures simultaneously but independently three distinct types of motor behaviour: (1) vertical activity, (2) horizontal activity, and (3) stationary movements.…”