title: Possibility of membrane reception of neurotransmitter in sea urchin early embryos.
abstract: 1. Methiodide derivatives of serotonin blockers--inmecarb and KYur-14 which poorly penetrate the cells specifically affect the pattern of cleavage division in half-embryos of Paracentrotus lividus and Scaphechinus mirabilis. 2. Specific [3H]8-OH-DPAT binding under conditions strictly limiting penetration of the ligand into the cells of Strongylocentrotus intermedius was also shown (Kd approximately 3 x 10(-10) M for a site with the greatest affinity). 3. On the basis of the data obtained it is concluded that neurotransmitter-specific membrane receptors may be present in sea urchin embryos during cleavage divisions. The "protosynapse" hypothesis is proposed which suggests the existence of a specific structure responsible for early blastomere interaction involving transmitters.
authors.affiliation: Laboratory of Embryophysiology, N.K. Koltzov Institute of Developmental Biology, Russian Acad. Sci., Moscow.
authors.forename: Y B
authors.initials: YB
authors.lastname: Shmukler
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000378:metabolism; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D004625:Embryo, Nonmammalian; D018377:Neurotransmitter Agents / Q000378:metabolism*; D011869:Radioligand Assay; D011956:Receptors, Cell Surface / Q000378:metabolism*; D012617:Sea Urchins; D012702:Serotonin Antagonists / Q000494:pharmacology
chemical_list: D018377:Neurotransmitter Agents; D011956:Receptors, Cell Surface; D012702:Serotonin Antagonists; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin