Effects of chronic haloperidol treatment on the expression of fear memory and fear memory extinction in the cued fear‐conditioned rats

Abstract Aim Impairments in emotional memory are frequently observed in several mental disorders, highlighting their significance as potential therapeutic targets. Recent research on the cued fear conditioning model has elucidated the neural circuits involved in fear memory processing. However, contradictory findings have been reported concerning the role of dopamine and the impact of dopamine D2 receptor (D2R) antagonists. There is notably limited knowledge regarding the clinical utility of chronic D2R antagonist treatments. This study aimed to uncover how such treatments affect fear memory processing. Methods We utilized a cued fear conditioning rat model and conducted chronic haloperidol treatment for 14 days. Subsequently, to investigate the effect of chronic haloperidol treatment on fear‐conditioned memory expression and extinction, we observed freezing behavior under exposure to a conditioned stimulus for 14 days. Results Chronic haloperidol treatment suppressed freezing time on the fear memory expression. In contrast, a single haloperidol administration enhanced the freezing time on fear memory expression and delayed extinction. Conclusion The results of this study suggest that chronic administration of antipsychotic drugs affects fear memory processing differently from single‐dose administration. This indicates that the effects of chronic D2R antagonist treatment are distinct from the nonspecific effects of the drugs. This study provides fundamental insights that may contribute to our understanding of therapeutic mechanisms for fear memory disorders related to D2R in the future

Effect of the Angiotensin-converting Enzyme Inhibitor Enalapril on Post-transplant Erythrocytosis

Post-transplant erythrocytosis (PTE) is increasingly recognized as a complication of kidney transplantation. In this study we report the effect of the angiotesin-converting enzyme (ACE) inhibitor enalapril on hematocrit (Ht) and erythropoietin in four patients with PTE. Four renal allograft recipients with Ht greater than 51 % were studied. Treatment was initiated with enalapril administered orally at a dose of 2.5 mg/day. All the patients had an increase of hemoglobin (Hb) (17.7 ± 0.64 g/dl), Ht (54.5 ± 1.29 %) and red blood cell count (REC) (584 ± 19.2 × 10⁴/μl). All patients responded to enalapril in 8 weeks with a significant decrease of Hb, Ht, and REC. In one patient, the downward trend was more rapid and sustained, and treatment had to be discontinued to prevent the development of anemia. Serum erythropoietin showed normal in all four patients and remained unchanged during the study, even after discontinuation of enalapril treatment. Serum creatinine remained relatively stable throughout the study. These results suggest that PTE may not be dependent upon circulating erythropoietin and that enalapril treatment may be an effective treatment of PTE without renal dysfunction

Beam Commissioning of SuperKEKB

International audienceIn this report, we describe the machine operation in the first 3 months of the Phase 1 commissioning of SuperKEKB. The beam commissioning is smoothly going on. Vacuum scrubbing, the optics corrections and others are described

The SuperKEKB Has Broken the World Record of the Luminosity

The SuperKEKB broke the world record of the luminosity in June 2020 in the Phase 3 operation. The luminosity has been increasing since then and the present highest luminosity is 4.65 x 10³⁴ cm⁻²s⁻¹ with β_{y}^{*} of 1 mm. The increase of the luminosity was brought with an application of crab waist, by increasing beam currents and by other improvements in the specific luminosity. In this paper, we describe what we have achieved and what we are struggling with. Finally, we mention a future plan briefly