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The suprachiasmatic nucleus (SCN) regulates daily rhythms in physiology and behavior. Previous studies suggest a critical role for neurons expressing vasoactive intestinal peptide (VIP) in coordinating rhythmicity and synchronization in the SCN. Here we examined the firing properties of VIP-expressing SCN neurons in acute brain slices. Active and passive membrane properties were measured in VIP and in non-VIP neurons during the day and at night. Current-clamp recordings revealed that both VIP and non-VIP neurons were spontaneously active, with higher firing rates during the day than at night. Average firing frequencies, however, were higher in VIP neurons (3.1 ± 0.2 Hz, day and 2.4 ± 0.2 Hz, night) than in non-VIP neurons (1.8 ± 0.2 Hz, day and 0.9 ± 0.2 Hz, night), both day and night. The waveforms of individual action potentials in VIP and non-VIP neurons were also distinct. Action potential durations (APD50) were shorter in VIP neurons (3.6 ± 0.1 ms, day and 2.9 ± 0.1 ms, night) than in non-VIP neurons (4.4 ± 0.3 ms, day and 3.5 ± 0.2 ms, night) throughout the light-dark cycle. In addition, afterhyperpolarization (AHP) amplitudes were larger in VIP neurons (21 ± 0.8 mV, day and 24.9 ± 0.9 mV, night) than in non-VIP neurons (17.2 ± 1.1 mV, day and 20.5 ± 1.2 mV, night) during the day and at night. Furthermore, significant day/night differences were observed in APD50 and AHP amplitudes in both VIP and non-VIP SCN neurons, consistent with rhythmic changes in ionic conductances that contribute to shaping the firing properties of both cell types. The higher day and night firing rates of VIP neurons likely contribute to synchronizing electrical activity in the SCN.
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http://dx.doi.org/10.1177/0748730415619745 | DOI Listing |
Front Physiol
August 2025
Center for Biomedical Research, National Research and Innovation Agency (BRIN), Cibinong, Indonesia.
Type 1 diabetes (T1D) is associated with severe metabolic dysregulation and organ complications such as hepatomegaly and nephropathy. While insulin therapy remains the cornerstone of treatment, there is growing interest in dietary interventions that modulate metabolic outcomes independently of insulin. This study aimed to investigate the effects of calorie restriction (CR) combined with time-restricted feeding (TRF) on metabolic and histological parameters in a high-fat diet-fed, streptozotocin-induced rat model of T1D.
View Article and Find Full Text PDFSleep Adv
June 2025
Sleep and Performance Research Center, Washington State University, Spokane, WA, United States.
Study Objectives: There are large individual differences in the homeostatic response to sleep deprivation, as reflected in slow wave sleep (SWS) and electroencephalogram (EEG) spectral power, which have largely been left unexplained. Recent evidence suggests the possible involvement of the activity-regulated cytoskeleton-associated protein () gene. Here we assessed the effects of the "c.
View Article and Find Full Text PDFJ Nurs Manag
September 2025
Division of Health Science, Graduate School of Medicine, The University of Osaka, 1-7 Yamadaoka, Suita, Osaka 565-0871, Japan.
In many developed countries, a rapidly aging population has increased healthcare demands and the proportion of older nurses in the workforce. This demographic shift requires nursing managers to have a deeper understanding of the physical demands on staff nurses, particularly older ones. In this paper, we aim to provide valuable insights for developing evidence-based strategies to improve work environments in hospital wards.
View Article and Find Full Text PDFNeuropsychopharmacol Rep
September 2025
Department of Anesthesiology and Pain Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan.
Background: Although opioid analgesics may influence sleep in patients with chronic pain, the association between strong opioid use and sleep characteristics remains unclear. This study aimed to explore differences in sleep status among chronic pain patients with varying levels of opioid use.
Methods: A total of 29 patients with chronic non-cancer pain who had been under treatment for more than 6 months were included.
J Ayurveda Integr Med
September 2025
Regional Ayurveda Research Institute, Poojappura, Thiruvananthapuram, Kerala, 695012, India; Under Central Council for Research in Ayurvedic Sciences, Ministry of AYUSH, Govt. of India, New Delhi, India.
This case report is the description of a devastating illness, Progressive Bulbar Palsy (PBP) of a sixty-seven years old male patient. He presented with complaints of slurred speech, hearing impairment, generalised weakness of limbs, weakened grip to hold objects in hand, difficulty to walk with normal speed, frequent dizzy feeling while walking, severe fatigue, increased anger, heaviness of head, depression, anxiety, decreased memory and headache for 1 year. When he consulted conventional medicine, in Magnetic Resonance Imaging (MRI) of brain, only 'Partial empty sella' and age related mild cerebral atrophy was detected and the patient was diagnosed PBP clinically.
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