Neural oscillations during cognitive processes in an App knock-in mouse model of Alzheimer's disease pathology.

Multiple animal models have been created to gain insight into Alzheimer's disease (AD) pathology. Among the most commonly used models are transgenic mice overexpressing human amyloid precursor protein (APP) with mutations linked to familial AD, resulting in the formation of amyloid β plaques, one of the pathological hallmarks observed in AD patients. However, recent evidence suggests that the overexpression of APP by itself can confound some of the reported observations.

Modulatory effect of 17-β estradiol on performance of ovariectomized rats on the Shock-Probe test.

17-β estradiol (E2) has been shown to modulate fear conditioning by influencing freezing behavior following re-exposure to either the conditioning context or a cue associated with shock. Fear-related behaviors other than freezing may be influenced differently by E2 replacement. Accordingly, the present study examined whether E2 modulates fear conditioning using the Shock-Probe test, which allows for the observation of multiple fear responses.

Systemic and intra-rhinal-cortical 17-β estradiol administration modulate object-recognition memory in ovariectomized female rats.

Previous studies using the novel-object-preference (NOP) test suggest that estrogen (E) replacement in ovariectomized rodents can lead to enhanced novelty preference. The present study aimed to determine: 1) whether the effect of E on NOP performance is the result of enhanced preference for novelty, per se, or facilitated object-recognition memory, and 2) whether E affects NOP performance through actions it has within the perirhinal cortex/entorhinal cortex region (PRh/EC). Ovariectomized rats received either systemic chronic low 17-β estradiol (E2; ~20 pg/ml serum) replacement alone or in combination with systemic acute high administration of estradiol benzoate (EB; 10 μg), or in combination with intracranial infusions of E2 (244.