Immunoidentification of CRF-like material in the intermaxillary glands during Bufo arenarum development

The presence of corticotropin-releasing factor-like material in the interma xillary glands was studied by immunocytochemical techniques during the meta morphosis of Bufo arenarum, The intermaxillary glands appeared at stage XV (midprometamorphosis) with CRF-like material slightly immunoreactive. These glands are located posterior to the premaxillae and between the nasal caps ules in the roof of the mouth and are formed of alveoli or tubules, During metamorphic climax, corticotropin-releasing factor-like material was identi fied strongly immunostained at the apices of the secretory cells. It was ob served that collecting ducts of the gland open to the anterior palatal surf ace suggesting that the secretion could be ingested by tadpoles. Our result s clearly showed that ir-CRF-like material present in the intermaxillary gl ands is ingested by tadpoles during metamorphosis and could play an importa nt role during amphibian development. (C) 2000 Harcourt Publishers Ltd.