[Neuroendocrine control of reproduction in worms].

In "worms", up to now only neurohormones produced by neurosecretory cells are known; no endocrine organ has been demonstrated. These neurohormones can be involved in the regulation of asexual reproduction (planarians). But their actions have been essentially studied in annelids (oligochaetes, polychaetes, hirudinae) where it is possible to give evidence of several types of functional regulations: endocrine control of sexual differentiation, gonadotropic action, conditioning of gametes development. The isolation of different neurohormones will allow to study and understand their differential action at the level of target cells and to better perceive the evolution of endocrine functions in the animal kingdom.