title: Enhancing the virulence of Streptococcus sobrinus in rats.
abstract: The purpose of this study was to explore the virulence of strains of Streptococcus sobrinus that had been re-isolated from a desalivated rat. Furthermore, we wished to determine the influence of desalivation on the acidogenicity of fasting and sucrose-pulsed dental plaque in rats infected by strains of S. sorbrinus. Experimental groups were formed and infected as follows: Group 1, desalivated animals, S. sorbrinus ATCC27352; Group 2, intact animals, infected as in Group 1; Group 3, desalivated animals, S. sorbrinus re-isolated from a desalivated animal that had been infected with the ATCC 27352 strain for five weeks; Group 4, intact animals, infected as in Group 3; Group 5, desalivated animals, S. sobrinus re-isolated from a desalivated animal that had been infected with the ATCC27352 strain for ten weeks; Group 6, intact animals, infected as in Group 5; Group 7, intact animals, no infection. All animals were fed cariogenic diet 2000 and sucrose-sweetened drinking water ad libitum. After five weeks, desalivated and intact animals that had been infected with isolates obtained from desalivated animals had significantly higher (p less than 0.05) smooth-surface-caries scores than did intact and desalivated animals infected with cultures of the original stock ATCC strain. Moreover, fasting plaque pH values were statistically lower in desalivated animals (Groups 1 and 3) than in intact animals (Groups 2, 6, and 7) (Turkey analysis, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: University of Rochester, Department of Dental Research, New York 14642.
authors.forename: K M
authors.initials: KM
authors.lastname: Madison
authors.forename: W H
authors.initials: WH
authors.lastname: Bowen
authors.forename: S K
authors.initials: SK
authors.lastname: Pearson
authors.forename: J L
authors.initials: JL
authors.lastname: Falany
mesh_terms: D000818:Animals; D003731:Dental Caries / Q000209:etiology / Q000382:microbiology*; D003773:Dental Plaque / Q000382:microbiology / Q000503:physiopathology; D004040:Dietary Carbohydrates / Q000494:pharmacology; D005215:Fasting; D006863:Hydrogen-Ion Concentration; D051381:Rats; D011919:Rats, Inbred Strains; D012463:Saliva / Q000382:microbiology / Q000502:physiology*; D012469:Salivary Glands / Q000502:physiology / Q000601:surgery; D013291:Streptococcus / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity*; D013395:Sucrose / Q000494:pharmacology; D014774:Virulence / Q000502:physiology
chemical_list: D004040:Dietary Carbohydrates; D013395:Sucrose