Ca[sup]$^2+$ excitability of glia to neuromodulator octopamine in Drosophila living brain is greater than that of neurons

Černe, Urška (avtor), Horvat, Anemari (avtor), Sanjković, Ena (avtor), Kozoderc, Nika (avtor), Kreft, Marko (avtor), Zorec, Robert (avtor), Scholz, Nicole (avtor), Vardjan, Nina (avtor)

Aim: Octopamine in the Drosophila brain has a neuromodulatory role similar to that of noradrenaline in mammals. After release from Tdc2 neurons, octopamine/tyramine may trigger intracellular Ca$^2+$ signaling via adrenoceptor-like receptors on neural cells, modulating neurotransmission. Octopamine/tyramine receptors are expressed in neurons and glia, but how each of these cell types responds to octopamine remains elusive. This study aimed to characterize Ca2+ responses of neurons and astrocytes to neuromodulatory octopamine signals. Methods: We expressed Ca$^2+$ indicator jGCaMP7b in specific cell type in adult Drosophila brains and performed intracellular Ca$^2+$ imaging in the brain optic lobes upon bath application of octopamine by confocal microscopy. Results: Octopamine-stimulated Ca$^2+$ responses in neurons were different from those of glial cells. The amplitude of octopamine-mediated Ca2+ signals in neurons was 3.4-fold greater than in astrocytes. However, astrocytes were more sensitive to octopamine; the median effective concentration that triggered Ca$^2+$ responses was nearly 6-fold lower in astrocytes than in neurons. In both cell types, Ca2+ transients are shaped by Gq and Gs protein-coupled octopamine/tyramine receptors. Our snRNA-seq database screening uncovered differential expression patterns of these receptors between brain cell types, which may explain the difference in Ca$^2+$ signaling. Conclusion: In the brain optic lobes, astrocytes, not neurons, appear to be the sole responders to low concentration octopamine signals, and therefore likely drive synaptic plasticity and visual processing. Given the interconnectivity of the optic lobes with other brain regions, octopaminergic signals acting through the optic lobe astrocytes may also influence higher-order brain functions including learning and memory.

• Jezik: Angleški jezik
• Ključne besede: Drosophila, Ca$^2+$ excitability, astrocytes, neuromodulator, neurons, octopamine, stress response
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: MF - Medicinska fakulteta
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2025
• Št. strani: 16 str.
• Številčenje: Vol. 241, iss. 2, art. e14270
• PID: 20.500.12556/RUL-184251
• UDK: 616-092
• ISSN pri članku: 1748-1716
• DOI: 10.1111/apha.14270
• COBISS.SI-ID: 223648003
• Datum objave v RUL: 02.07.2026

Gradivo je del revije

• Naslov: Acta physiologica
• Založnik: Wiley, Scandinavian Psychological Society
• ISSN: 1748-1716
• COBISS.SI-ID: 2917396

Licence

• Licenca: CC BY-NC 4.0, Creative Commons Priznanje avtorstva-Nekomercialno 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by-nc/4.0/deed.sl
• Opis: Licenca Creative Commons, ki prepoveduje komercialno uporabo, vendar uporabniki ne rabijo upravljati materialnih avtorskih pravic na izpeljanih delih z enako licenco.

Sekundarni jezik

• Jezik: Slovenski jezik
• Ključne besede: drozofila, Ca2+ ekscitabilnost, astrociti, nevromodulator, nevroni, oktopamin, odziv na stres