Orexin neuropeptides modulate the hippocampal-dependent memory through basolateral amygdala interconnections.

Orexin neuropeptides have functional roles in hippocampal-dependent memory formation via the consolidation and retrieval of passive avoidance and spatial memories. The effects of these neuropeptides have been confirmed on the induction of long-term potentiation (LTP). The orexinergic system seems to have modulatory effects by sending projection fibers to several brain parts, such as the hippocampus and amygdala. Orexin neuropeptides activate the neural circuits of the basolateral amygdala during different arousal events with various emotional loads. Therefore, this system plays a vital role in creating appropriate behavioral reactions and responses particular to the situation. This review aimed to report new progression and advances in the hippocampus function in memory by focusing on its relationship with the amygdala through the orexinergic system.

Psychometric Evaluation of Persian Version of Hope Scale in Iranian Patients With Cancer.

BACKGROUND AND PURPOSE: Adult Hope Scale is one of the most popular tools for hope measuring. The study aimed to evaluate the psychometric properties of the Persian Version of Hope Scale among Iranian patients with cancer. METHODS: In this methodological study, patients with cancer (n = 400) were recruited by convenience sampling from June to December 2019. The construct and content validity and reliability of the scale were evaluated. RESULTS: A two-factor structure for the scale was indicated with the factors being optimism life, and despair that explained 60.483% of the total variance of the scale. The model has the goodness of fit and acceptable internal consistency (Cronbach's alpha: .701-.897). CONCLUSIONS: The Persian Version of Hope Scale demonstrated acceptable validity and reliability among patients with cancer.

Development and Validation of the Knowledge and Attitude Scale Toward COVID-19 Pandemic Breaking Transmission Chain (KA-C) Among Iranian Population.

Objectives: We aimed to develop a scale and evaluate this scale's validity and reliability to measure factors affecting people's knowledge and attitudes toward the pandemic breaking transmission chain. Methods: This exploratory mixed-method study was carried out in two phases: (1) item generation using literature reviews and interviews and, (2) item reduction by psychometric assessments of the developed scale. The face, content, construct (exploratory and confirmatory factor analysis), convergent, and discriminant validity of the scale were assessed in the Iranian population (n = 500) from March to June 2020. The Composite Reliability (CR) and the internal consistency correlation coefficient were estimated. Results: The Knowledge and Attitude Scale Toward COVID-19 Pandemic Breaking Transmission Chain (KA-C) among the Iranian population included 18 items. Two factors with a whole variance of 66.05% were identified by exploratory factor analysis. Factors were labeled as "health literacy" and "home health empowerment." The confirmatory factor analysis showed the goodness of fit. The CR of the scale for first and second factors were 0.965 and 0.833 receptively. The scale's internal consistency correlation coefficient was acceptable (Cronbach's alpha = 0.960 and 0.823, average interitem correlation = 0.643 and 0.635, McDonald's omega = 0.963 and 0.829, for the first and second factor, receptively). Conclusion: The KA-C scale can be exerted to screen the people's knowledge and attitude about the COVID-19 pandemic breaking the transmission chain as a valid and reliable scale for further policymaking, health care providers, and for a multi-dimensional psychosocial assessment of the pandemic period.

The Effect of Orexin Receptor Antagonism on Quinpirole-Induced Compulsive-Like Checking Behavior in Rats.

The orexinergic system supposedly plays a role in stress circuits for arousing behaviors during anxiety, suggesting that it may play a role also in neural circuits mediating the compulsive behavior characteristic of obsessive-compulsive disorder (OCD). This study aims to investigate the roles of the orexinergic system in the development of OCD behaviors, using as preparation the induction of compulsive checking by chronic treatment with the D2/D3 agonist, quinpirole. Repeated injections of quinpirole (0.5 mg/kg, twice per week for a total of 10 injections) were used to induce compulsive checking. In separate groups of rats, OX1R (SB334867-A; 10 µg i.c.v) and OX2R (TCS-OX2-29; 10 µg i.c.v) receptor antagonists were co-administered together with quinpirole. Checking behavior in a large open field was measured after the first, fifth, and tenth injections of the drugs. SB334867-A attenuated checking behavior and the level of anxiety. TCS-OX2-29 administration ameliorated anxiety but did not block the development of compulsive checking. Orexin 1 receptors seem to play a more critical role than orexin 2 receptors in the induction of compulsive checking. Considering that the quinpirole sensitization model of OCD involves activation of dopamine systems and sensitization to quinpirole, it is suggested that neural interaction between orexigenic and dopamine systems may be important in the pathogenesis of OCD.