Intraperitoneal administration of arginine vasotocin (AVT) induces anorexigenic and anxiogenic actions via the brain V1a receptor-signaling pathway in the tiger puffer, Takifugu rubripes

Ryo Nagamine; Norifumi Konno; Tomoya Nakamachi; Hajime Matsubara; Kouhei Matsuda

doi:10.1016/j.peptides.2024.171239

Intraperitoneal administration of arginine vasotocin (AVT) induces anorexigenic and anxiogenic actions via the brain V1a receptor-signaling pathway in the tiger puffer, Takifugu rubripes

Peptides. 2024 May 7:178:171239. doi: 10.1016/j.peptides.2024.171239. Online ahead of print.

Authors

Ryo Nagamine¹, Norifumi Konno², Tomoya Nakamachi², Hajime Matsubara³, Kouhei Matsuda⁴

Affiliations

¹ Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan.
² Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan; Laboratory of Regulatory Biology, Faculty of Science, Academic Assembly, University of Toyama, Toyama 930-8555, Japan.
³ Noto Center for Fisheries Science and Technology, Kanazawa University, Ossaka, Noto-cho, Ishikawa 927-0552, Japan.
⁴ Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan; Laboratory of Regulatory Biology, Faculty of Science, Academic Assembly, University of Toyama, Toyama 930-8555, Japan. Electronic address: kmatsuda@sci.u-toyama.ac.jp.

PMID: 38723948
DOI: 10.1016/j.peptides.2024.171239

Abstract

Arginine vasotocin (AVT) is produced mainly in the hypothalamus and as a neurohypophyseal hormone peripherally regulates water-mineral balance in sub-mammals. In addition, AVT-containing neurons innervate several areas of the brain, and AVT also acts centrally as both an anorexigenic and anxiogenic factor in goldfish. However, it is unclear whether these central effects operate in fish in general. In the present study, therefore, we investigated AVT-like immunoreactivity in the brain of the tiger puffer, a cultured fish with a high market value in Japan and also a representative marine teleost species, focusing particularly on whether AVT affects food intake and psychomotor activity. AVT-like immunoreactivity was distributed higher in the ventral region of the telencephalon, the hypothalamus and midbrain. Intraperitoneal (IP) administration of AVT at 100 pmol g^-1 body weight (BW) increased the immunoreactivity of phosphorylated ribosomal proteinS6 (RPS6), a neuronal activation marker, in the telencephalon and diencephalon, decreased food consumption and enhanced thigmotaxis. AVT-induced anorexigenic and anxiogenic actions were blocked by IP co-injection of a V1a receptor (V1aR) antagonist, Manning compound (MC) at 300 pmol g^-1 BW. These results suggest that AVT acts as an anorexigenic and anxiogenic factor via the V1aR-signaling pathway in the tiger puffer brain.

Keywords: AVT; Anorexigenesis; Anxiogenesis; Intraperitoneal administration; Tiger puffer.