title: Dissociation of adrenocorticotropin and corticosterone as well as aldosterone secretion during stress of hypoglycemia in vasopressin-deficient rats.
abstract: OBJECTIVE
  In vasopressin-deficient rat pups stressor-induced adrenocorticotropin (ACTH) and corticosterone elevations markedly dissociate. We have shown recently that during the postnatal period mineralocorticoid secretion is more sensitive to stressor exposure than that of glucocorticoids. We have therefore hypothesized that in vasopressin-deficient pups during hypoglycemia, a stressor triggering aldosterone release mainly via ACTH, aldosterone release will change in parallel with ACTH. An additional aim was to reveal at which stage of the development occurs the shift from aldosterone to corticosterone as primarily stressor-induced adrenocortical hormone.
  
  
  METHODS
  Vasopressin-deficient (di/di) and control Brattleboro rats were used both postnatally (10-day-old rats) and in adulthood.
  
  
  RESULTS
  Hypoglycemia induced similar ACTH elevations in pups and adults with significantly lower levels in di/di rats. In contrast, vasopressin-deficiency resulted in elevated resting aldosterone and stressor-induced corticosterone levels in pups without genotype differences in adults. Thus, aldosterone levels also dissociated from ACTH secretion. During stress, pups showed only minimal corticosterone increase, with relatively high aldosterone elevation. Resting levels of gluco- and mineralocorticoid receptor mRNA were smaller, while corticosterone-deactivating enzyme (11β-HSD2) mRNA level were higher in the hippocampus of 10-day-old rats compared to adults.
  
  
  CONCLUSIONS
  AVP does not seem to substantially regulate the stressor-induced aldosterone production, but both hormones contribute to salt-water regulation. Postnatally higher stressor-induced aldosterone than corticosterone production was still detectable in 40-day-old rats, although to a lesser extent, supporting a shift in the balance between stressor-induced glucocorticoid and mineralocorticoid hormone release throughout the development occurring in rats after postnatal day 40.
authors.affiliation: Department of Behavioral Neurobiology, Institute of Experimental Medicine, 1083 Budapest, Szigony 43, Hungary.
authors.forename: János
authors.initials: J
authors.lastname: Varga
authors.affiliation: Laboratory of Molecular Neuroendocrinology, Institute of Experimental Medicine, 1083 Budapest, Szigony 43, Hungary.
authors.forename: Szilamér
authors.initials: S
authors.lastname: Ferenczi
authors.affiliation: Laboratory of Molecular Neuroendocrinology, Institute of Experimental Medicine, 1083 Budapest, Szigony 43, Hungary.
authors.forename: Krisztina J
authors.initials: KJ
authors.lastname: Kovács
authors.affiliation: Laboratory of Pharmacological Neuroendocrinology, Institute of Experimental Endocrinology, BMC, Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia.
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Csáno
authors.affiliation: Laboratory of Pharmacological Neuroendocrinology, Institute of Experimental Endocrinology, BMC, Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia.
authors.forename: Barbora
authors.initials: B
authors.lastname: Prokopova
authors.affiliation: Laboratory of Pharmacological Neuroendocrinology, Institute of Experimental Endocrinology, BMC, Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia.
authors.forename: Daniela
authors.initials: D
authors.lastname: Jezova
authors.affiliation: Department of Behavioral Neurobiology, Institute of Experimental Medicine, 1083 Budapest, Szigony 43, Hungary. Electronic address: zelena.dora@koki.mta.hu.
authors.forename: Dóra
authors.initials: D
authors.lastname: Zelena
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000450:Aldosterone / Q000378:metabolism*; D000818:Animals; D003345:Corticosterone / Q000378:metabolism*; D017353:Gene Deletion; D007003:Hypoglycemia / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D011910:Rats, Brattleboro; D013315:Stress, Psychological; D014667:Vasopressins / Q000235:genetics / Q000378:metabolism*
chemical_list: D014667:Vasopressins; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone
keywords: 11β-HSD1; 11β-HSD2; Brattleboro rat; Glucocorticoid receptor; Mineralocorticoid receptor; Potassium