Angiogênese, vascularização e uso do ultrassom Doppler colorido na avaliação de estruturas ovarianas / Angiogenesis, vascularization and color Doppler ultrasonography to evaluate ovarian structures

A angiogênese ocorre como um processo fisiológico essencial para o crescimento e o desenvolvimento normal dos tecidos. A adequada formação da rede vascular é um passo limitante para o bom funcionamento do ovário, pois garante a disponibilidade de oxigênio, nutrientes, hormônios e substratos, bem como a transferência de diferentes hormônios para as células-alvo. Nos últimos anos, o fluxo sanguíneo local do ovário tem sido analisado por meio da ultrassonografia com Doppler colorido, técnica que permite analisar individualmente os folículos e o corpo lúteo. Esta revisão de literatura aborda os mais relevantes aspectos da reestruturação vascular do ovário durante o ciclo estral em fêmeas domésticas de grande porte.(AU)

Angiogenesis occurs as a physiologic process and is essential for normal growth and development of tissue. The ovary and its structures need adequate vascular network to ensure the availability of oxygen, nutrients, hormones, substrate, and ensure the transfer of different hormones to target cells. Then, the proper formation of this network is a limiting step for the proper functioning of this organ in general. In recent years, the local blood flow of the ovary, has been examined by color Doppler ultrasound, being able to analyze the individual follicles and the corpus luteum. This review will board the relevant aspects of the restructuring vascular ovary during the estrous cycle in female domestic large.(AU)

Angiogênese, vascularização e uso do ultrassom Doppler colorido na avaliação de estruturas ovarianas / Angiogenesis, vascularization and color Doppler ultrasonography to evaluate ovarian structures

A angiogênese ocorre como um processo fisiológico essencial para o crescimento e o desenvolvimento normal dos tecidos. A adequada formação da rede vascular é um passo limitante para o bom funcionamento do ovário, pois garante a disponibilidade de oxigênio, nutrientes, hormônios e substratos, bem como a transferência de diferentes hormônios para as células-alvo. Nos últimos anos, o fluxo sanguíneo local do ovário tem sido analisado por meio da ultrassonografia com Doppler colorido, técnica que permite analisar individualmente os folículos e o corpo lúteo. Esta revisão de literatura aborda os mais relevantes aspectos da reestruturação vascular do ovário durante o ciclo estral em fêmeas domésticas de grande porte.

Angiogenesis occurs as a physiologic process and is essential for normal growth and development of tissue. The ovary and its structures need adequate vascular network to ensure the availability of oxygen, nutrients, hormones, substrate, and ensure the transfer of different hormones to target cells. Then, the proper formation of this network is a limiting step for the proper functioning of this organ in general. In recent years, the local blood flow of the ovary, has been examined by color Doppler ultrasound, being able to analyze the individual follicles and the corpus luteum. This review will board the relevant aspects of the restructuring vascular ovary during the estrous cycle in female domestic large.

Follicular growth and plasma progesterone patterns in Bos indicus x Bos taurus heifers submitted to different PGF2/progesterone-based synchronization protocols

The effect of different levels of progesterone (P4) concentrations on follicle growth and ovulatory capacity was evaluated in 40 crossbred Bos indicus x Bos taurus cyclic heifers submitted to distinct PGF2α + progesterone-based protocols. Heifers in CIDR_PGF8 group (n = 10) received 2.0 mg i.m. estradiol benzoate (EB) and a new controlled internal drug release containing 1.9 g of progesterone (CIDR) on day 0 of study. At the time of CIDR withdrawal (day 8), heifers received an i.m. injection of PGF2α and 24 h later a second EB i.m. injection (0.5 mg). The three other groups received EB injections and CIDR insertion/withdrawal as aforementioned, except that an i.m. injection of PGF2α was administered on day 5. In addition, heifers in the CIDR_PGF5 group (n = 10) received a new CIDR, while heifers in theCIDR1x_PGF5 (n = 9) and CIDR2x_PGF5 (n = 11) groups received a previously used CIDR for 8 and 14 days, respectively. Heifers that received a PGF2α injection on day 5 showed lower circulating P4 than heifers treated on day 8 (CIDR_PGF5 = 1.98 ± 0.21 ng/ml; CIDR1x_PGF5 = 1.69 ± 0.17 ng/ml and CIDR2x_PGF5 = 1.33 ± 0.08 ng/ml versus CIDR_PGF8 = 3.31 ± 0.45 ng/ml). The dominant follicle (DF) growth rate was slower in those heifers receiving PGF2α injection on day 8 (CIDR_PGF8 = 0.72 ± 0.13 mm/day) than groups treated on day 5 (CIDR_PGF5 = 0.96 ± 0.12 mm/day; CIDR1x_PGF5 = 1.06 ± 0.15 mm/day and CIDR2x_PGF5 = 1.01 ± 0.06mm/day). In consequence, preovulatory follicle diameter on day 10 was smaller in those animals injected on day 8 (CIDR_PGF8 = 8.81 ± 6.7 mm) than in those treated on day 5 (CIDR_PGF5 = 10.00 ± 0.58 mm CIDR1x_PGF5 = 10.5 ± 0.69 mm and CIDR2x_PGF5 = 10.5 ± 0.35 mm). For heifers receiving PGF2α injection on day 5, no significant differences on plasma P4 concentrations, folliculargrowth rate and DF diameters were observed among heifers that received new or previously used CIDR inserts. These results suggest that the presence of corpus luteum during synchronization protocols is the main factor responsible for the increase in the plasma P4 concentrations and inhibition of DF growth.(AU)

Follicular growth and plasma progesterone patterns in Bos indicus x Bos taurus heifers submitted to different PGF2/progesterone-based synchronization protocols

The effect of different levels of progesterone (P4) concentrations on follicle growth and ovulatory capacity was evaluated in 40 crossbred Bos indicus x Bos taurus cyclic heifers submitted to distinct PGF2α + progesterone-based protocols. Heifers in CIDR_PGF8 group (n = 10) received 2.0 mg i.m. estradiol benzoate (EB) and a new controlled internal drug release containing 1.9 g of progesterone (CIDR) on day 0 of study. At the time of CIDR withdrawal (day 8), heifers received an i.m. injection of PGF2α and 24 h later a second EB i.m. injection (0.5 mg). The three other groups received EB injections and CIDR insertion/withdrawal as aforementioned, except that an i.m. injection of PGF2α was administered on day 5. In addition, heifers in the CIDR_PGF5 group (n = 10) received a new CIDR, while heifers in theCIDR1x_PGF5 (n = 9) and CIDR2x_PGF5 (n = 11) groups received a previously used CIDR for 8 and 14 days, respectively. Heifers that received a PGF2α injection on day 5 showed lower circulating P4 than heifers treated on day 8 (CIDR_PGF5 = 1.98 ± 0.21 ng/ml; CIDR1x_PGF5 = 1.69 ± 0.17 ng/ml and CIDR2x_PGF5 = 1.33 ± 0.08 ng/ml versus CIDR_PGF8 = 3.31 ± 0.45 ng/ml). The dominant follicle (DF) growth rate was slower in those heifers receiving PGF2α injection on day 8 (CIDR_PGF8 = 0.72 ± 0.13 mm/day) than groups treated on day 5 (CIDR_PGF5 = 0.96 ± 0.12 mm/day; CIDR1x_PGF5 = 1.06 ± 0.15 mm/day and CIDR2x_PGF5 = 1.01 ± 0.06mm/day). In consequence, preovulatory follicle diameter on day 10 was smaller in those animals injected on day 8 (CIDR_PGF8 = 8.81 ± 6.7 mm) than in those treated on day 5 (CIDR_PGF5 = 10.00 ± 0.58 mm CIDR1x_PGF5 = 10.5 ± 0.69 mm and CIDR2x_PGF5 = 10.5 ± 0.35 mm). For heifers receiving PGF2α injection on day 5, no significant differences on plasma P4 concentrations, folliculargrowth rate and DF diameters were observed among heifers that received new or previously used CIDR inserts. These results suggest that the presence of corpus luteum during synchronization protocols is the main factor responsible for the increase in the plasma P4 concentrations and inhibition of DF growth.