The effect of temperature on the action of thyroid hormone and prolactin in larvae of the salamander Hynobius retardatus

摘要: Abstract To elucidate the environmental factors and endocrine mechanisms which are responsible for inducing neoteny in salamander Hynobius retardatus , effect of temperature on growth metamorphosis this amphibian, as well actions thyroid hormone prolactin at low temperature, were studied. (1) The larvae cultivated 10° was significantly delayed compared with that 22°, but eventually completed. At 4°, never occurred, even after 2 years. (2) Exogenously administered accelerated or ineffective kept whether by injection immersion. (3) If a higher concentration given single to cultured an appreciable acceleration observed transferring 22°. (4) Unlike hormone, promoted 4°.