They studied brain samples from mice and rats that were raised with chronic exposure to nicotine and had developed nicotine dependence — similar to a heavy smoker going through two packs a day. (sciencedaily.com)
The researchers followed up with an analysis of mouse and human brain samples. (sciencedaily.com)
The protocol for collecting frozen brain samples is followed when tissue can be collected within 12 hours of death. (chimpanzeebrain.org)