title: Regulation of plasma glucose and sulfate excretion in Pacific hagfish, Eptatretus stoutii is not mediated by 11-deoxycortisol.
abstract: The goal of this study was to identify whether Pacific hagfish (Eptatretus stoutii) possess glucocorticoid and mineralocorticoid responses and to examine the potential role(s) of four key steroids in these responses. Pacific hagfish were injected with varying amounts of cortisol, corticosterone or 11-deoxycorticosterone (DOC) using coconut oil implants and plasma glucose and gill total-ATPase activity were monitored as indices of glucocorticoid and mineralocorticoid responses. Furthermore, we also monitored plasma glucose and 11-deoxycortisol (11-DOC) levels following exhaustive stress (30 min of agitation) or following repeated infusion with SO42-. There were no changes in gill total-ATPase following implantation with any steroid, with only very small statistical increases in plasma glucose noted in hagfish implanted with either DOC (at 20 and 200mgkg-1at 7 and 4days post-injection, respectively) or corticosterone (at 100mgkg-1at 7days post-injection). Following exhaustive stress, hagfish displayed a large and sustained increase in plasma glucose. Repeated infusion of SO42-into hagfish caused increases in both plasma glucose levels and SO42-excretion rate suggesting a regulated glucocorticoid and mineralocorticoid response. However, animals under either condition did not show any significant increases in plasma 11-DOC concentrations. Our results suggest that while there are active glucocorticoid and mineralocorticoid responses in hagfish, 11-DOC does not appear to be involved and the identity and primary function of the steroid in hagfish remains to be elucidated.
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Clifford
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Diabetes & Nutritional Sciences Division, Kings College, London, UK; Faculty of Health and Life Sciences, University of Suffolk, Suffolk, UK.
authors.forename: Nicolas R
authors.initials: NR
authors.lastname: Bury
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Aaron G
authors.initials: AG
authors.lastname: Schultz
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: James D
authors.initials: JD
authors.lastname: Ede
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
authors.forename: Brendan L
authors.initials: BL
authors.lastname: Goss
authors.affiliation: Bamfield Marine Sciences Centre, Bamfield, BC, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada. Electronic address: greg.goss@ualberta.ca.
authors.forename: Greg G
authors.initials: GG
authors.lastname: Goss
mesh_terms: D000818:Animals; D053898:Biosynthetic Pathways; D001786:Blood Glucose / Q000378:metabolism*; D000074263:Coconut Oil; D003345:Corticosterone / Q000096:biosynthesis; D003350:Cortodoxone / Q000378:metabolism*; D006196:Hagfishes / Q000502:physiology*; D010938:Plant Oils / Q000494:pharmacology; D013312:Stress, Physiological; D013431:Sulfates / Q000097:blood / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D010938:Plant Oils; D013431:Sulfates; D000074263:Coconut Oil; D003345:Corticosterone; D003350:Cortodoxone
keywords: Agnatha; Glomerular filtration rate; Glucocorticoid; Ionoregulation; Mineralocorticoid; Steroid biosynthesis