Vasotocin and hydrin 2 (vasotocinyl-Gly) in the African toad Bufo regularis: study under various environmental conditions.

Abstract

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.

• Authors: J Chauvet, Y Ouedraogo, G Michel, R Acher
• Journal: Comparative biochemistry and physiology. Comparative physiology (Comp Biochem Physiol Comp Physiol) Vol. 104 Issue 3 Pg. 497-502 (Mar 1993) England
• PMID: 8097151 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Neurophysins
• Protein Precursors
• Arginine Vasopressin
• hydrin 2
• Oxytocin
• Vasotocin

Topics

• Amino Acid Sequence
• Animals
• Arginine Vasopressin (metabolism)
• Biological Assay
• Bufonidae
• Chromatography, High Pressure Liquid
• Dehydration (physiopathology)
• Environment
• Female
• In Vitro Techniques
• Molecular Sequence Data
• Neurophysins (metabolism)
• Osmolar Concentration
• Oxytocin
• Pituitary Gland, Posterior (metabolism)
• Pregnancy
• Protein Precursors (metabolism)
• Rats
• Spectrophotometry, Ultraviolet
• Vasotocin (analogs & derivatives, metabolism)