title: Adenosine deaminase activity in serum, erythrocytes and lymphocytes of rats infected with Leptospira icterohaemorrhagiae.
abstract: Leptospirosis is a systemic disease of humans and domestic animals, mainly dogs, cattle and swine. The course of human leptospirosis varies from mild to severe fatal forms and the most severe form of human leptospirosis is principally caused by Leptospira interrogans serovar icterohaemorrhagiae (L. icterohaemorrhagiae). The enzyme adenosine deaminase (ADA) plays an important role in the production and differentiation of blood cells. The aim of this study was to evaluate the activity of ADA in serum, erythrocytes and lymphocytes of rats infected with L. icterohaemorrhagiae, as compared with non-infected rats. Twenty-four adult rats, divided into two uniform groups (A and B) were used for the enzymatic assays. The animals in Group B were inoculated intraperitoneally with 2×10(8) leptospires/rat, and the rodents in Group A (control) were not-inoculated. Blood collection was performed on days 5 and 15 post-infection (PI) and the blood used to assess the ADA activity. The infection by L.icterohaemorrhagiae altered erythrocyte count, hemoglobin concentration and hematocrit, causing a decrease in all these parameters on day 15 PI. Lymphocytes decreased significantly on day 15 PI, and ADA activity in serum was inhibited in infected rats on days 5 and 15 PI and its activity in erythrocytes were increased on day 5 PI. On day 5 PI, we found an increase in ADA activity in erythrocytes of infected rats. No correlation was observed between hematocrit and erythrocyte ADA activity on days 5 and 15 PI. The ADA activity was inhibited in rats infected on day 15 PI. A positive correlation (r(2)=60) was also observed between the number of lymphocytes and ADA activity in lymphocytes on day 15 PI (P<0.05). In conclusion, our results showed that the ADA activity is altered in serum, lymphocytes and erythrocytes in experimental infection by L.icterohaemorrhagiae in rats, concomitantly with hematological parameters.
authors.affiliation: Department of Microbiology and Parasitology, Universidade Federal de Santa Maria, Brazil. tonin_alexandre@yahoo.com.br
authors.forename: Alexandre A
authors.initials: AA
authors.lastname: Tonin
authors.forename: Victor C
authors.initials: VC
authors.lastname: Pimentel
authors.forename: Aleksandro S
authors.initials: AS
authors.lastname: da Silva
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: de Azevedo
authors.forename: Viviane C G
authors.initials: VC
authors.lastname: Souza
authors.forename: Patrícia
authors.initials: P
authors.lastname: Wolkmer
authors.forename: João F P
authors.initials: JF
authors.lastname: Rezer
authors.forename: Manoel R T
authors.initials: MR
authors.lastname: Badke
authors.forename: Daniela B R
authors.initials: DB
authors.lastname: Leal
authors.forename: Maria Rosa C
authors.initials: MR
authors.lastname: Schetinger
authors.forename: Silvia G
authors.initials: SG
authors.lastname: Monteiro
authors.forename: Sonia T A
authors.initials: ST
authors.lastname: Lopes
mesh_terms: D000243:Adenosine Deaminase / Q000097:blood / Q000378:metabolism*; D000818:Animals; D004906:Erythrocyte Count; D004912:Erythrocytes / Q000201:enzymology*; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D007919:Leptospira; D007922:Leptospirosis / Q000097:blood / Q000201:enzymology*; D018655:Lymphocyte Count; D008214:Lymphocytes / Q000201:enzymology*; D008297:Male; D051381:Rats; D013997:Time Factors
chemical_list: D006454:Hemoglobins; D000243:Adenosine Deaminase