[Development of a bioassay from gonadal cellular cultures of the snail Helix aspersa: influence of nerve ganglion extracts on the synthetic activity of the target cells].

To realize bioassays a primary culture method was carried out with dissociated cells from the garden snail gonads. ADN and protein syntheses of gonadal cells were estimated using the liquid scintillation method. The gonadal cells were obtained from either adults of Petits Gris and Gros Gris, or young Gros Gris. The results were remarkably homogeneous. The brain extracts added to the culture medium had an inhibitory dose dependent effect on the synthetic activity of gonadal cells. The effected bioassays permit quantitative estimation on the variations of the brain extracts effect in relation to the physiological states of the snail and on the evolution of target cells' receptors during the growth of Gros Gris.