[Cholinergic regulation of the sea urchin embryonic and larval development].
Choline esters of polyenoic fatty acids block cleavage divisions of sea urchins and evoke the formation of one-cell multinuclear embryos. If the fatty acids AA-Ch or DHA-Ch are added at the mid or late blastula stage, many cells are extruded, forming extra-embryonic cell clusters near the animal pole of embryos or larvae. Both effects are prevented by dimethylaminoethyl esters of polyenoic fatty acids (AA-DMAE or DHA-DMAE) or their 5-hydroxytryptamides. Nicotinic acetylcholine receptor antagonists, imechine, d-tubocurarine or QX-222 provide partial protection against AA-Ch or DHA-Ch. The organophosphate pesticide, chlorpyrifos, or a combination of (-)-nicotine + phorbol 12-myristate 13-acetate, also evoke the mass extrusion of transformed embryonic cells at the animal pole of larvae. These effects are similarly antagonized by AA-DMAE, DHA-DMAE, or fatty acids 5-hydroxytryptamides. Taking together, these results suggest that AA-Ch and DHA-Ch act on sea urchin embryos and larvae as agonists of acetylcholine receptors, whereas AA-DMAE and DHA-DMAE act as antagonists. The ability of fatty acids 5-hydroxytryptamides to prevent the effects of AA-Ch or DHA-Ch may be due to restoration of the normal dynamic balance of cholinergic and serotonergic signaling during cleavage divisions and gastrulation.
Buznikov
G A
GA
N. K. Koltzov Institute of Developmental Biology of the Russia Acad. Sci., 26 Vavilov St., Moscow 117808, Russia.
Bezuglov
V V
VV
Nikitina
L A
LA
Slotkin
T A
TA
Lauder
J M
JM
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D004390:Chlorpyrifos / Q000494:pharmacology; D002794:Choline / Q000031:analogs & derivatives / Q000494:pharmacology; D018679:Cholinergic Agonists / Q000494:pharmacology; D018680:Cholinergic Antagonists / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D004281:Docosahexaenoic Acids / Q000494:pharmacology; D004625:Embryo, Nonmammalian; D007814:Larva; D012617:Sea Urchins / Q000196:embryology* / Q000502:physiology*
D001095:Arachidonic Acids; D018679:Cholinergic Agonists; D018680:Cholinergic Antagonists; D002800:Cholinesterase Inhibitors; C442433:N,N-dimethylaminoethyl arachidonate; C442432:arachidonoylcholine; D004281:Docosahexaenoic Acids; D004390:Chlorpyrifos; D002794:Choline; D000109:Acetylcholine