The olfactory hypothesis for salmon imprinting and homing to their natal stream is well known, but the endocrine hormonal control mechanisms of olfactory memory formation in juveniles and retrieval in adults remain unclear. In brains of hatchery-reared underyearling juvenile chum salmon (Oncorhynchus keta), thyrotropin-releasing hormone gene expression increased immediately after release from a hatchery into the natal stream, and the expression of the essential NR1 subunit of the N-methyl-D-aspartate receptor increased during downstream migration. Gene expression of salmon gonadotropin-releasing hormone (sGnRH) and NR1 increased in the adult chum salmon brain during homing from the Bering Sea to the natal hatchery. Thyroid hormone treatment in juveniles enhanced NR1 gene activation, and GnRHa treatment in adults improved stream odour discrimination. Olfactory memory formation during juvenile downstream migration and retrieval during adult homing migration of chum salmon might be controlled by endocrine hormones and could be clarified using NR1 as a molecular marker.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4754751 | PMC |
http://dx.doi.org/10.1038/srep21102 | DOI Listing |
In Vitro Cell Dev Biol Anim
January 2025
Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON, N2L 3C5, Canada.
Long dsRNA induces the expression of type I interferons (IFNs) and IFN-stimulated genes (ISGs) to establish an antiviral state. When induced prophylactically, this antiviral state can reduce the severity and mortality of viral infections. One of the limiting factors in delivering dsRNA in animal models is the lack of an effective carrier that protects the dsRNA from degradation in the extracellular space.
View Article and Find Full Text PDFConserv Physiol
December 2024
Department of Marine Bioscience, Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8564, Japan.
The physiological performance of ectotherms is influenced by temperature, raising concerns about the impact of global warming on ectotherms. Understanding the relationship between ecologically relevant temperatures and the physiological performance of ectotherms provides a basis for assessing their resilience to changing environments. Absolute aerobic scope (AAS) is a functional metric of the thermal performance of aquatic ectotherms.
View Article and Find Full Text PDFPhotodermatol Photoimmunol Photomed
January 2025
Department of Medical Science and Pharmaceutical Engineering, Soonchunhyang University, Asan, Republic of Korea.
Background: Exposure to ultraviolet (UV) light promotes reactive oxygen species (ROS) production and metalloproteinase (MMP) 1 expression, leading to skin damage. Several studies have reported that protein-rich fish byproducts from enzymatic hydrolysis exhibited a variety of health benefits such as antioxidant and anti-inflammation. In the current study, we investigated the protective effect of protein hydrolysate from salmon byproduct (SBPH) in ultraviolet B (UVB)-irradiated human dermal fibroblasts (HDFs) and zebrafish.
View Article and Find Full Text PDFInterspecific competition can significantly impact marine ecosystems by affecting species distributions and abundances. Understanding how sympatric species utilize available food helps identify potential competition and its effects when resources are limited. Here, we applied a suite of analytical methods (diet analysis, stable isotopes, and biomass estimates) to identify potential competitive interactions among North Pacific pelagic predators.
View Article and Find Full Text PDFMicroorganisms
November 2024
Department of Aqualife Medicine, Chonnam National University, Yeosu 59626, Republic of Korea.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!