Enhanced apoptosis and decreased ampa receptors are involved in deficit in fear memory in rin1 knockout rats

Activated cell-cycle CDK4/CyclinD1-pRB-E2F1 signaling pathway is involved in the apoptosis of dorsal raphe nucleus in the rat model of PTSD

Dysregulation of the dorsal raphe nucleus (DRN) has been revealed to contribute to cognitive and arousal impairments associated with post-traumatic stress disorder (PTSD) in an animal model. In our research an acute exposure to single prolonged stress (SPS) was used to establish PTSD rat model and the effects related to cell-cycle signaling pathway in DRN were examined. Apoptosis in DRN was detected by TUNEL staining, showing that DRN apoptosis number was sharply increased after SPS. SPS triggered cell-cycle CDK4/CyclinD1-pRB-E2F1 signal pathway. Treatment with CDK4 inhibitor Abemaciclib successfully attenuated the DRN apoptosis and rescued decreased spatial learning and memory abilities in SPS rats, indicating that activation of CDK4/CyclinD1-pRB-E2F1 pathway was involved in DRN apoptosis, which may be one of the pathogenesis for PTSD.

How do stupendous cannabinoids modulate memory processing via affecting neurotransmitter systems?

In the present study, we wanted to review the role of cannabinoids in learning and memory in animal models, with respect to their interaction effects with six principal neurotransmitters involved in learning and memory including dopamine, glutamate, GABA (γ-aminobutyric acid), serotonin, acetylcholine, and noradrenaline. Cannabinoids induce a wide-range of unpredictable effects on cognitive functions, while their mechanisms are not fully understood. Cannabinoids in different brain regions and in interaction with different neurotransmitters, show diverse responses. Previous findings have shown that cannabinoids agonists and antagonists induce various unpredictable effects such as similar effect, paradoxical effect, or dualistic effect. It should not be forgotten that brain neurotransmitter systems can also play unpredictable roles in mediating cognitive functions. Thus, we aimed to review and discuss the effect of cannabinoids in interaction with neurotransmitters on learning and memory. In addition, we mentioned to the type of interactions between cannabinoids and neurotransmitter systems. We suggested that investigating the type of interactions is a critical neuropharmacological issue that should be considered in future studies.

Rat models of human diseases and related phenotypes: a systematic inventory of the causative genes

The laboratory rat has been used for a long time as the model of choice in several biomedical disciplines. Numerous inbred strains have been isolated, displaying a wide range of phenotypes and providing many models of human traits and diseases. Rat genome mapping and genomics was considerably developed in the last decades. The availability of these resources has stimulated numerous studies aimed at discovering causal disease genes by positional identification. Numerous rat genes have now been identified that underlie monogenic or complex diseases and remarkably, these results have been translated to the human in a significant proportion of cases, leading to the identification of novel human disease susceptibility genes, helping in studying the mechanisms underlying the pathological abnormalities and also suggesting new therapeutic approaches. In addition, reverse genetic tools have been developed. Several genome-editing methods were introduced to generate targeted mutations in genes the function of which could be clarified in this manner [generally these are knockout mutations]. Furthermore, even when the human gene causing a disease had been identified without resorting to a rat model, mutated rat strains (in particular KO strains) were created to analyze the gene function and the disease pathogenesis. Today, over 350 rat genes have been identified as underlying diseases or playing a key role in critical biological processes that are altered in diseases, thereby providing a rich resource of disease models. This article is an update of the progress made in this research and provides the reader with an inventory of these disease genes, a significant number of which have similar effects in rat and humans.