Egashira_1994_Nihon.Shinkei.Seishin.Yakurigaku.Zasshi_14_245

We have devised a method for the procurement and breeding of aged rats used for aiding in the development of drugs for disease, involving Alzheimer's disease and cerebrovascular dementia. The changes in choline acetyltransferase (ChAT), acetylcholinesterase (AChE), muscarinic receptor binding (mAChR) and Na(+)-dependent high affinity choline uptake (HACU) are generally consistent with age-dependent declines in cholinergic neurotransmission, although these decreases may include differences in strain/species, sex, tissue sampling and assay procedures. So, the choice of time points during the life cycle selected for comparison between young and aged rats is particularly important when using laboratory animals. These observations support the utility of the senescent rat model in studying aging and development of nootropic drugs.