<abstract xmlns="http://www.w3.org/1999/xhtml"><p>There are several findings indicating that the endocannabinoid system (ECS) is an important factor, acting in multiple ways in regulating reproductive function but changes of this system in the bovine endometrium have rarely been investigated; therefore, this study was designed to consider an association between endometrial ECS expression and different stages of the estrous cycles. MRNA expressions of the ECS were investigated during the late luteal phase and estrus using real-time PCR. Following estrous synchronization of sixteen Holstein dairy cows (34±1.3 kg/day of milk production), using two PGF2α injections given 14 days apart, at 30 and 44 days in milk (DIM), blood samples and ultrasonography (US) were performed every other day from the day of second PGF2α injection (44 DIM) until the start of the next estrous cycle (67±2 DIM) to verify CL development and ovulation. Based on blood and US results endometrial tissue was collected on days 16 (late luteal phase) and 21 (estrus) of the synchronized estrous cycle (ovulation = d 0). Real-time PCR analysis of ECS mRNA expression revealed endocannabinoid receptor (CNR2), diacylglycerol lipase (DAGL), cyclooxygenase-2 (COX-2), fatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGLL) had significant fold differences when comparing two different stages of the estrous cycle (late luteal phase vs. estrus). CNR2 and DAGL showed 2.01 and 2.57 fold increase, respectively (P=0.04 and P=0.02), in estrous cows. Among the analyzed genes <italic>FAAH</italic> (P=0.01) and <italic>MGLL</italic> (P=0.02) were significantly down-regulated in estrous cows, with a 5.01- and 2.44-fold difference in mRNA expression, respectively. Overall, this study highlights an association between the expression of the ECS in the bovine endometrium and stage of the estrous cycle.</p></abstract>

There are several findings indicating that the endocannabinoid system (ECS) is an important factor, acting in multiple ways in regulating reproductive function but changes of this system in the bovine endometrium have rarely been investigated; therefore, this study was designed to consider an association between endometrial ECS expression and different stages of the estrous cycles. MRNA expressions of the ECS were investigated during the late luteal phase and estrus using real-time PCR. Following estrous synchronization of sixteen Holstein dairy cows (34±1.3 kg/day of milk production), using two PGF2α injections given 14 days apart, at 30 and 44 days in milk (DIM), blood samples and ultrasonography (US) were performed every other day from the day of second PGF2α injection (44 DIM) until the start of the next estrous cycle (67±2 DIM) to verify CL development and ovulation. Based on blood and US results endometrial tissue was collected on days 16 (late luteal phase) and 21 (estrus) of the synchronized estrous cycle (ovulation = d 0). Real-time PCR analysis of ECS mRNA expression revealed endocannabinoid receptor (CNR2), diacylglycerol lipase (DAGL), cyclooxygenase-2 (COX-2), fatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGLL) had significant fold differences when comparing two different stages of the estrous cycle (late luteal phase vs. estrus). CNR2 and DAGL showed 2.01 and 2.57 fold increase, respectively (P=0.04 and P=0.02), in estrous cows. Among the analyzed genes FAAH (P=0.01) and MGLL (P=0.02) were significantly down-regulated in estrous cows, with a 5.01- and 2.44-fold difference in mRNA expression, respectively. Overall, this study highlights an association between the expression of the ECS in the bovine endometrium and stage of the estrous cycle.

The Role of Endocannabinoid System Based on mRNA Expression During the Late Luteal Phase and Estrus in the Bovine Endometrium

Sari Agricultural Sciences and Natural Resources University

Annals of Animal Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

There are several findings indicating that the endocannabinoid system (ECS) is an important factor, acting in multiple ways in regulating reproductive function...

The Role of Endocannabinoid System Based on mRNA Expression During the Late Luteal Phase and Estrus in the Bovine Endometrium

Published Online: Oct 30, 2019

Page range: 979 - 989

Received: Mar 02, 2019

Accepted: Jul 08, 2019

DOI: https://doi.org/10.2478/aoas-2019-0044

Keywords
endocannabinoid system (ECS), estradiol, progesterone, real-time PCR

© 2019 Essa Dirandeh et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The Role of Endocannabinoid System Based on mRNA Expression During the Late Luteal Phase and Estrus in the Bovine Endometrium

Published Online: Oct 30, 2019

Page range: 979 - 989

Received: Mar 02, 2019

Accepted: Jul 08, 2019

DOI: https://doi.org/10.2478/aoas-2019-0044

Keywordsendocannabinoid system (ECS), estradiol, progesterone, real-time PCR

© 2019 Essa Dirandeh et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
endocannabinoid system (ECS), estradiol, progesterone, real-time PCR