The footfault test as a screening tool in the 6-hydroxydopamine rat model of Parkinson's disease.

The administration of 6-hydroxydopamine (6-OHDA) into the nigrostriatal pathway is a rat model of Parkinson's disease (PD). The footfault test is a behavioural task in which rodents have their motor functions assessed. Here, we observed that unilaterally 6-OHDA-lesioned animals show a context-induced ipsilateral rotational behaviour when placed on the footfault apparatus for 3 min and this may be used as index to detect lesioned animals. Our results showed a sensitivity and specificity of 100% for lesions higher than 94% and 64%, respectively (ROC curve: AUC=0.988). A binary logistic regression model showed an expB=1.116 (95% CI, 1.007-1.236) and C=-9.081+/-4.554 (p=0.046) using the nigral tyrosine hidroxylase immunocontent as standard (each unit represents a 10%-lesion extension). Additionally, the footfault test was more sensitive than apomorphine challenging at 1mg/kg when these tests were carried out days apart and it was less sensitive than methylphenidate at 40 mg/kg (sign test, p<0.05). Therefore, the footfault test may be very useful in the PD animal model for screening animals since it is fast and simple and it does not require a drug to induce rotational activity.

A new tracking system for the measurement of diel locomotor rhythms in the Norway lobster, Nephrops norvegicus (L.).

The Norway lobster, Nephrops norvegicus (L.), is a deep-water burrowing decapod of high commercial value. Diel variations in trawl captures are produced by population rhythms of burrow emergences related to day-night cycles. Rhythms seem to be different in males and females since catches show variations in sex ratios depending on the season. Our hypothesis is that the diel rhythm of activity in this species can be distinguished in three different behavioural sets, the durations of which show gender-related modulation: door-keeping, proximal-, and distal-emergence from the burrow. Our aim is to detail the functioning of a new tracking system allowing the durations of these three behavioural components to be determined. Movement of animals was detected by subdividing aquaria into different zones by means of three rows of infrared-emitting and -receiving photodiodes in which blue light emitters were also integrated for the generation of light cycles. We recorded movement patterns in adult males and females (n=20) exposed to a standard photoperiod regime (i.e., 12 h; monochromatic at 480 nm of 5 lx) over 12 days. Marked diel nocturnal rhythms were reported at all barriers, with activity peaks diffused over the night at the burrow entrance and located at the day-night transition at other barriers (i.e., crepuscular peaks that decreased in the next few hours of darkness). Mean total activity was significantly higher for females than males at the burrow entrance (i.e., door-keeping behaviour). Males had significantly higher activity at other locations (proximal- and distal-emergence behaviours).

A novel automated rat catalepsy bar test system based on a RISC microcontroller.

Catalepsy tests performed in rodents treated with drugs that interfere with dopaminergic transmission have been widely used for the screening of drugs with therapeutic potential in the treatment of Parkinson's disease. The basic method for measuring catalepsy intensity is the "standard" bar test. We present here an easy to use microcontroller-based automatic system for recording bar test experiments. The design is simple, compact, and has a low cost. Recording intervals and total experimental time can be programmed within a wide range of values. The resulting catalepsy times are stored, and up to five simultaneous experiments can be recorded. A standard personal computer interface is included. The automated system also permits the elimination of human error associated with factors such as fatigue, distraction, and data transcription, occurring during manual recording. Furthermore, a uniform criterion for timing the cataleptic condition can be achieved. Correlation values between the results obtained with the automated system and those reported by two independent observers ranged between 0.88 and 0.99 (P<0.0001; three treatments, nine animals, 144 catalepsy time measurements).