Animals 7 Male Rats animal 7 male 7 rat 7 Article 5 animal experiment 5 controlled study 5 nonhuman 5 Rats, Sprague-Dawley 4 Sprague Dawley rat 4 animal tissue 4 Disease Models, Animal 3 animal model 3 disease model 3 human 3 metabolism 3 physiology 3 Behavior, Animal 2 Conditioning, Classical 2 Humans 2 adult 2 animal behavior 2 chemistry 2 conditioned reflex 2 cytology 2 in vitro study 2 in vivo study 2 protein expression 2