Vasotocin and hydrin 2 (vasotocinyl-Gly) in the African toad Bufo regularis: study under various environmental conditions.
1. The neurohypophysial osmoregulatory hormones of the African toad Bufo regularis, a species adapted to estivate under dry and hot conditions, have been investigated. Vasotocin and hydrin 2 (vasotocinyl-Gly) have been identified by their retention times in high-pressure reverse-phase liquid chromatography and coelution with synthetic peptides, their pharmacological properties (vasotocin) and microsequencing. 2. Vasotocin-associated neurophysin (MSEL-neurophysin type) has been characterized by its N-terminal amino acid sequence. 3. In toads subjected to dehydration by evaporation (20% weight loss) or to osmotic stress by immersion in 2% NaCl for 3 hr (6% weight loss), the molar ratio hydrin 2/vasotocin (about 2:1) remained similar to the one observed in control animals. 4. In toads exposed to saline solution, there was a large decrease (roughly 30%) in the amounts of both hormones in the neuro-hypophysis. Environmental conditions for distinct secretions of vasotocin and hydrin 2 remain to be found.
Chauvet
J
J
Laboratory of Biological Chemistry, University of Paris, France.
Ouedraogo
Y
Y
Michel
G
G
Acher
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism; D001681:Biological Assay; D002025:Bufonidae; D002851:Chromatography, High Pressure Liquid; D003681:Dehydration / Q000503:physiopathology; D004777:Environment; D005260:Female; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D009481:Neurophysins / Q000378:metabolism; D009994:Osmolar Concentration; D010121:Oxytocin; D010904:Pituitary Gland, Posterior / Q000378:metabolism*; D011247:Pregnancy; D011498:Protein Precursors / Q000378:metabolism; D051381:Rats; D013056:Spectrophotometry, Ultraviolet; D014668:Vasotocin / Q000031:analogs & derivatives* / Q000378:metabolism
D009481:Neurophysins; D011498:Protein Precursors; D001127:Arginine Vasopressin; C060258:hydrin 2; D010121:Oxytocin; D014668:Vasotocin