title: The antitumor drug 3-nitrobenzothiazolo(3,2-a)quinolinium chloride (NBQ): effects on lens regeneration and interaction with DNA of Notophthalmus viridescens.
abstract: We have studied the effect of 3-nitrobenzothiazolo(3,2-a)quinolinium (NBQ) on the regeneration of the lens in adult newt Notophthalmus viridescens. NBQ has marked cytotoxic effects in tumor cells, intercalates DNA, and was found to enhance lens regeneration. Newt liver DNA was isolated, and the thermal denaturation temperature (Tm) determined to be 76.6% +/- 0.8%. The G-C content was determined to be 44.0% +/- 0.4% and 45.0% +/- 0.1%. Parameters of NBQ binding to newt DNA were determined by spectrophotometric methods and compared with those obtained for calf thymus and Micrococcus lysodeikticus. The association constant, K(o), was found to be 1.1 x 10(+5) M-1 with a site-size parameter, n, of 8.7 nucleotides. No explanation is apparent for the paradoxical stimulation of lens regeneration.
authors.affiliation: Department of Chemistry, Natural Sciences Faculty, University of Puerto Rico.
authors.forename: F A
authors.initials: FA
authors.lastname: Gonzalez
authors.forename: M
authors.initials: M
authors.lastname: Llende
authors.forename: A
authors.initials: A
authors.lastname: Baez
authors.forename: J R
authors.initials: JR
authors.lastname: Ortiz
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D004247:DNA / Q000378:metabolism*; D007364:Intercalating Agents / Q000378:metabolism / Q000494:pharmacology*; D007908:Lens, Crystalline / Q000187:drug effects* / Q000502:physiology; D009673:Notophthalmus viridescens; D011806:Quinolinium Compounds / Q000378:metabolism / Q000494:pharmacology*; D012038:Regeneration / Q000187:drug effects*; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
chemical_list: D000970:Antineoplastic Agents; D007364:Intercalating Agents; D011806:Quinolinium Compounds; C038668:3-nitrobenzothiazolo(3,2-a)quinolinium; D004247:DNA