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The effects of 17β-estradiol (E2) or estradiol benzoate (EB) on PGF2α release were studied in bred-non-pregnant and pregnant Nelore beef heifers. The day of timed artificial insemination (TAI) was designated day 0 (D0), and a single treatment was given on D14. All heifers also received an intravaginal P4 device on D14, and were randomly assigned to three groups: Control (C, P4 device only, n = 12); E2 (1 mg E2 + 9 mg P4, n = 10); or EB (1 mg, n = 10). Blood samples were collected hourly for 8 hours after treatment (Hours 0-8) to measure plasma concentrations (pg/mL) of a PGF2α metabolite (PGFM). The P4 device was removed on D22 and pregnancy was diagnosed on D28. Pregnancy rate was not different among groups (C, n = 7/12; E2, n = 5/10; EB, n = 5/10). More (P0.05) heifers had a CV-identified prominent PGFM pulse (peak of100 pg/mL) in E2 group (6/10) than in EB (1/10) and C (0/12) groups. Hourly concentration of PGFM for Hours 0 to 8 showed significant effects of group and hour and an interaction of group by hour but did not show an interaction of group or hour with pregnancy status. In preliminary post-hoc analyses, PGFM concentrations during Hours 0 to 8 and pulse characteristics were analyzed within each pregnancy status. For the non-pregnant heifers, a group-by-hour interaction was detected tentatively indicating an increase (P0.005) in PGFM concentrations in E2 group from Hours 4 to 6 and in EB group at Hours 5 and 6. Maximum PGFM concentration during Hours 0 to 8 did not differ (P0.1) between E2 (124 ± 23) and EB (110 ± 30) groups, but was greater (P0.05) in each group than in C (32 ± 3). Furthermore, PGFM concentrations of pulses at the peak, amplitude, and area under pulse curve (pg/mL/h) were greater (P0.05) in E2 group than in C group whereas the EB group did not differ (P0.1) from the other groups. For pregnant heifers, no effects of group, hour, or their interaction were detected in PGFM concentrations during the hourly sessions, except that maximum PGFM concentration was greater (P0.05) in E2 than in EB and C groups. In addition, the number of prominent pulses was greater in E2 group than in Control or EB groups. In conclusion, PGFM increased earlier and in greater concentration combined for bred-non-pregnant and pregnant heifers treated 14 days after TAI with 1 mg E2 plus 9 mg P4 than with 1 mg EB. Tentatively, a positive effect for each of E2 and EB on PGFM concentrations was attenuated in pregnant heifers.

O conhecimento do processo de luteolise dentro da fisiologia reprodutiva se torna importante para que ocorra a compreensao do reconhecimento materno da gestacao e seja possivel formular estrategias anti-luteoliticas que visem manter esta fase conferindo aumentos na eficiencia reprodutiva e produtiva. Durante o processo de luteolise, o tecido luteal sofre mudancas bruscas na capacidade esteroidogenica, vascularizacao e remodelamento, resultando em substituicao da glândula por tecido conjuntivo, sendo a PGF2α o principal determinante na inducao espontânea da luteolise em bovinos. Simultaneamente, ocorre um intimo processo entre as relacoes anatomicas que compreende o ovario, utero e suas vascularizacoes. A exposicao do utero a interacao coordenada entre P4, E2 e ocitocina aliada a expressao de seus receptores sao essenciais para a secrecao pulsatil de PGF2α pelo endometrio a qual induzira a luteolise. Nesta regressao do corpo luteo (CL), estao envolvidos ainda os hormonios (LH, prolactina, cortisol) e varias substâncias vasoativas (oxido nitrico, VEGF, EG-VEGF, bFGF, END-1, AngII). A concentracao de PGF2α pode ser representada pela mensuracao sanguinea da concentracao de seu metabolito 13,14-dihidro-15-ceto- PGF2α (PGFM) sendo a pulsatilidade da secrecao de PGF2α durante os periodos pre-luteolitico, luteolitico e pos-luteolitico mensuravel pelo aumento na concentracao de PGFM. Neste artigo de revisao, sera possivel compreender e discutir os principais aspectos endocrinos e moleculares que ocorrem com as mudancas morfofuncionais no CL durante o processo de luteolise fisiologica em femeas bovinas.

Inflammation causes increases in the level of matrix metalloproteinases (MMPs), which, in central nervous system (CNS), are associated with neuroinflammation and disruption of blood-brain barrier. Analysis of cerebrospinal fluid (CSF) is pivotal for detecting diseases in CNS and, although a specific diagnosis may not be achieved, this analysis is helpful to confirm the diagnosis or to rule out relevant differential diagnoses. This study examined the levels of MMP-2 and MMP-9 in the CSF of dogs using gelatin zymography to verify possible alterations in these enzymes during natural systemic infection with Leishmania chagasi. Latent and active forms of MMP-2 were detected in some dogs of both groups, with high levels in the control group. In contrast, latent and active forms of MMP-9 were detected only in some animals with leishmaniasis. These results clearly demonstrate that MMP-9 is elevated in CSF of dogs with visceral leishmaniasis (VL). Although these results are preliminary, they suggest that MMP-9 might play a role in disruption of blood-brain barrier and/or blood-CSF barrier. While the presence of MMPs in CSF is not a condition exclusive to VL, their presence and persistence in CSF supports the hypothesis of an inflammatory state within CNS of dogs with VL.

International audience; ABSTRACT The aim of this study was to evaluate the blood leukocytes and the MMP-2 and -9 expression in the hoof laminar tissue of horses undergoing intraluminal small colon obstruction. Laparotomy and the small colon obstruction was performed in eight healthy horses, inserting a ball in the intestinal lumen. The ball was inflated to 80 mmHg pressure and the occlusion was maintained for 4 hours. The blood was collectedBlood samples were taken before the obstruction (M0), immediately after intestinal clearance (M4), and every 12 hours until completeuntil 72 hours (M12, M24, M36, M48, M60 and M72). The hoof biopsies were performed at M0, M4, and M72 and the samples were subjected to zymography analysis. There was an increase in leukocytes in M12 and M24, due to the increase in segmented neutrophils and band neutrophils, which decreased as of M36. According to zymography technique not observed changes were not not observed in MMP-2 and -9, possibly due to the low intensity of the small colon lesions. Wherefore, it is concludedIn conclusion, that the inflammatory changes resulting from small colon obstruction were not enough to cause changes in the expression of MMP-2 and -9 in the hoof laminar tissue.; RESUMO O objetivo deste estudo foi avaliar a expressão das MMP-2 e MMP-9 no tecido laminar do casco e o perfil leucocitário de equinos submetidos à obstrução intraluminal do cólon menor. Realizaram-se laparotomia e obstrução do cólon menor de oito equinos hígidos, utilizando-se uma bola inserida no lúmem intestinal. A bola foi inflada à pressão de 80mmHg e a obstrução foi mantida por quatro horas. Foram realizadas coletas sanguíneas antes da obstrução (M0), imediatamente após a desobstrução (M4) e a cada 12 horas após M4, até completar 72 horas (M12, M24, M36, M48, M60 e M72). As biópsias de casco foram realizadas em M0, M4 e M72, e as amostras foram submetidas à análise zimográfica. Foi observado aumento nos leucócitos em M12 e M24, decorrente do aumento de neutrófilos segmentados e bastonetes, os quais diminuíram a partir de M36. Segundo a técnica zimográfica, não se observaram alterações nos valores de MMP-2 e -9, possivelmente devido à baixa intensidade das lesões ocasionadas no cólon menor. Com isso, conclui-se que as alterações inflamatórias decorrentes da obstrução do cólon menor não foram suficientes para ocasionar alterações na expressão das MMP-2 e -9 no tecido laminar podal.