The distribution of alpha-MSH containing neurons was studied by immunofluorescence in the brain of the frog Rana ridibunda. Most immunoreactive cell bodies were found in the ventral hypothalamic area. A rich network of fluorescent fibers was observed in the ventral infundibular region, coursing towards the preoptic area and the ventral telencephalon. Some fibers, directed backwards, project into median eminence. By means of a specific radioimmunoassay, the concentrations of alpha-MSH immunoreactive material has been determined in 10 different regions of the brain. The highest concentrations were observed in the infundibular and the preoptic regions. Using the immunogold technique, electron microscopy showed that immunostaining was restricted to 70-100 nm dense core vesicles in positive cell bodies and fibers. These results suggest that, in addition to well known hormonal (melanotropic) activity, alpha-MSH could play the role of a neurotransmitter in the frog brain.
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Biochemistry (Mosc)
December 2024
Institute of the Biological Problems of the North, Far Eastern Branch of the Russian Academy of Sciences, Magadan, 630058, Russia.
Hypoxia poses a serious challenge for all animals; however, certain animals exhibit a remarkable resilience in the case of prolonged and severe hypoxia. The Siberian wood frog is a unique amphibian capable of surviving for up to several months at almost complete anoxia. We investigated changes in the metabolome of at the onset of hypoxia (day 1) and within 1 h of reoxygenation after a long-term hypoxia using H NMR.
View Article and Find Full Text PDFPigment Cell Melanoma Res
January 2025
Department of Cell Biology and Anatomy, Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.
Circadian regulation of skin pigmentation is essential for thermoregulation, ultraviolet (UV) protection, and synchronization of skin cell renewal. This regulation involves both cell-autonomous photic responses and non-cell-autonomous hormonal control, particularly through melatonin produced in a light-sensitive manner. Photosensitive opsins, cryptochromes, and melatonin regulate circadian rhythms in skin pigment cells.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2025
Department of Biotechnology and Department of Integrative Food, Bioscience and Biotechnology (BK21 FOUR), Chonnam National University, Gwangju, 61186, South Korea. Electronic address:
Methylergometrine has widely been used pharmacologically to treat conditions such as pain, addiction, vasoconstriction, migraines, and Parkinson's disease. Despite its side effects, it is used as a therapeutic agent and research material for various diseases based on its natural potential; however, the regulatory effect of its interaction with the nicotinic acetylcholine receptor (nAChR) has not yet been investigated. The α3β4 nAChR is an ion channel essential for neurotransmission within the sympathetic, parasympathetic, and autonomic nervous systems.
View Article and Find Full Text PDFJ Neurochem
January 2025
Department of Biotechnology and Life Sciences, Laboratory of Cellular and Molecular Physiology, University of Insubria, Varese, Italy.
Front Neurol
November 2024
Division of Neurobiology, Faculty of Biology, Ludwig-Maximilians University Munich, Planegg, Germany.
Background: Energetic aspects of neuronal activity have become a major focus of interest given the fact that the brain among all organs dominates the oxygen consumption. At variance with the importance of neuroenergetics, the knowledge about how electrical activity and metabolism is correlated in defined neuronal populations is still rather scarce.
Results: We have estimated the ATP consumption in the two physiologically well characterized populations of frog central vestibular neurons, with tonic and phasic firing patterns, respectively.
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