eCG e densidade vascular em úteros bovinos / eCG and vascular density of bovine uterus

AUTOR(ES)
DATA DE PUBLICAÇÃO

2009

RESUMO

Follicle dynamic, as well as the uterus preparation for gestation, is dependent of an adequate vascularization establishment. Currently, many studies point towards the importance of eCG treatment following fixed-time artificial insemination (FTAI), in a manner to improve ovulation and gestational rates. Moreover, eCG have been implicated in angiogenesis, leading to important changes in uterine blood flow and vascularization. Thus, the present study was designed to investigate the influence of eCG on the endometrial and myometrial thickness and area; on the caliber and area of the uterine artery of the ipsilateral horn; and, on endometrial and myometrial uterine vascular density of cows submitted to sincronization (control group), stimulation (stimulated group), and superovulatory (superovulated group) treatments. For that, we used 16 cows with body score between 2 and 3, randomly distributed into the 3 above described groups: the cows of the control group (n = 5) did not receive eCG, while the cows of the stimulated group (n = 6) and superovulated group 3 (n = 5) received, respectively, 400 UI and 2000 UI of eCG at days 4 and 8 after the protocol beginning. For endometrial and myometrial measurements, as well as for uterine artery caliber and area analysis, ultrasonographic evaluations were done at day 5 after ovulation. At day 6, the animals were slaughtered, the uterus were harvested and fixed in 4% paraformaldehyde. In order to analyze the vascular density, immunohistochemistry for KDR detection and blood vessels counting by stereology were performed. In all studied groups, treatments did not influence either uterine wall thickness or area. In the superovulated animals, the uterine artery presented higher caliber than in the control ones (P<0.05). Endometrial vascular density of stimulated animals in the ipsilateral uterine horn was lower when compared to that of the control (P<0.05),and in the superovulated, vascular density was lower in the myometrium (P<0.05). These results suggest that the endometrial vascularization increase following eCG treatment, described by other groups, is probably influenced by the concept, not only by the treatment. Moreover, the influence of eCG in the uterus could be dependent of both the hormonal dosis and the estrous cycle phase.

ASSUNTO(S)

densidade vascular ecg ecg estimulação estimulation superovulação superovulation Útero uterus vascular density

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