Anatomical organization of CRF‐and AVT‐like systems in the newt hypothalamus and the effects of localized lesion to the posterior hypothalamus on serum aldosterone and corticosterone

Abstract

The anatomical organization of the preoptico‐hypophysial systems, and in particular of CRF‐like and AVT‐like fibres, throughout the posterior hypothalamus of the crested newt, Triturus crista‐tus carnifex Laur. was investigated immunohistochemically. The effects on interrenal activity of central and bilateral lesions in the posterior hypothalamus were also evaluated immunohistochemically and biochemically. Bilateral lesions which interrupted both CRF‐like and AVT‐like fibre systems resulted in a decrease in serum corticosterone and aldosterone, while central lesions rostral to the median eminence caused slighter decreases in the steroid levels and did not affect so dramatically the CRF‐like afferences to the median eminence; the pars nervosa was frequently atrophied.

Key words:

• Posterior hypothalamus
• CRF
• Aldosteron and corticosterone serum levels