ACTH-stimulated cortisol release from head kidney of rainbow trout is modulated by glucose concentration.

摘要: SUMMARY To assess the hypothesis that cortisol release in rainbow trout is modulated by glucose levels, we first evaluated [basal and adrenocorticotropic hormone (ACTH)-regulated] head kidney tissue superfused with medium reflecting hypoglycaemic, normoglycaemic or hyperglycaemic conditions. Next, from fragments static incubations was assessed parallel changes parameters related to synthesis (mRNA abundance of StAR, P450scc, 3βHSD 11βH) GK-mediated glucosensing mechanism (levels glycogen glucose, activities GK, GSase PK, mRNA levels GLUT-2, Kir6.x-like SUR-like). We then effects two inhibitors transport, cytochalasin B phlorizin, on production mechanisms. The ACTH-induced proved be concentration such increased occurs under high decreased ACTH-stimulated when transport inhibited B. can associated as enhanced genes also noted medium. Specific GK immunoreactivity cortisol-producing cells (not chromaffin cells) further substantiates production. In contrast, no compatible those release/synthesis presence ACTH were for any other putative glucosensor mechanisms based LXR, SGLT-1 Gnat3. These combined results are evidence a fish linking non-pancreatic like circulating levels. relationship evident regulated (ACTH-dependent) pathway this suggests acute stress conditions important regulation release.