Animals
Two cohorts, respectively of 12 and 24 adult Lister Hooded male rats
(Envigo, UK), were trained prior to surgery on reinforced T-maze
alternation. The first cohort had 8 iDREADDs and 4 GFP-control animals.
The second cohort had 12 iDREADDs and 12 GFP-control animals, giving
totals of 20 in the iDREADDs group and 16 GFP- controls. At the time of
surgery all rats weighed between 236-360g. They were housed in pairs in
a temperature-controlled room, under a 12h light/dark cycle. For all
behavioural experiments, water was available ad libitum . The rats
were put on a food-restricted diet whereby they were still able to gain
weight. None of the rats weighed less than 85% of their free-feeding
weight.
All animals were randomly assigned to one of the virus conditions and
underwent the same surgical and behavioural procedures. The experimenter
was not, however, blind to the group membership of the animals. All
experimental procedures were carried out in accordance with the UK
Animals (Scientific Procedures) Act 1986 and were approved by the local
Cardiff University Ethics Committee.