Effects of cholinergic drugs on cell interactions during fertilization and early development of the sea urchin Paracentrotus lividus
Pieroni, M.; Falugi, C.
Bollettino della Societa Italiana di Biologia Sperimentale 68(2): 113-119
1992
ISSN/ISBN: 0037-8771 PMID: 1380817 Document Number: 398636
In the present work we tested the effects of cholinergic drugs on the early development of P. lividus. Fertilization was performed in the presence of cholinergic drugs, and the embryos were fixed after 2 hours, when the controls (untreated) completed the second segmentation cleavage. We identified four classes of stages in the development of the embryos affected by the drugs, i.e.: unhatched zygotes, first cleaved stage, second cleaved stage (= unaffected), and anomalous embryos. Statistical analysis indicated that that drugs with analogous action mechanism caused similar alterations in the distribution of the treated embryos in these four classes. This finding supports the hypothesis of the presence of a complete "pre-nervous" cholinergic system, with a true cholinergic role. It is tempting to speculate that this system is involved in the first cell to cell interactions during early segmentation and possibly in the block to polyspermy.