title: Isonicotinic acid hydrazide inhibits cell population growth during teratogenesis of chick embryo.
abstract: In chick embryos treated with a 4 hr pulse of 7.2 X 10(-5) M isonicotinic acid hydrazide (INH) the cell population growth is inhibited with an increased population doubling time. Teratogenised blastoderm cells complete their ongoing cell cycle and arrest in G1 phase. A chase with an equimolar concentration of pyridoxal-5-phosphate restores the growth rate after a lag of 4 hr equivalent to the duration of treatment with INH. Presumptive mesoblast cells invaginated through the primitive streak and neuroectoblast cells induced prior to the application of INH differentiate, while the teratogen inhibits morphogenesis and organization of organ primordia.
authors.affiliation: Department of Zoology, University of Poona, India.
authors.forename: M V
authors.initials: MV
authors.lastname: Joshi
authors.forename: V B
authors.initials: VB
authors.lastname: Shah
authors.forename: S P
authors.initials: SP
authors.lastname: Modak
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002642:Chick Embryo; D007538:Isoniazid / Q000037:antagonists & inhibitors / Q000633:toxicity*; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D013723:Teratogens / Q000633:toxicity*
chemical_list: D013723:Teratogens; D011732:Pyridoxal Phosphate; D007538:Isoniazid