Ultrasonography in Experimental Reproductive Investigations on Rats

Ultrasonography in experimental reproductive investigations on rats. The objective orders to establish an ultrasonography approach on Sprague-Dawley rats. To design experimental models in reproductive and a gynecology investigation.

Introduction of ultrasound. Images were obtained by using a high-resolution ultrasound bio-microscope. And 40 MegaHertz transfuser.

Preparing rats for imaging. Ah-nas-ah ties it down in induction chamber. Removed animal from induction chamber and immediately placed its mouth with the nose cone connected to the anesthesia system.

Remove fur from the costal margin to the caudal abdomen with hair clip and depilatory cream. Place the anesthetized rat in a supine position. On a heating pad.

Gently insert a rectal probe to monitor body temperature. The transfuser was placed in a stationary holder. And could be moved along the vertical axis.

The rat was placed on a examination stage. And moved us through to horizontal axis. You can move the transfuser by a manually operated joystick.

Or by your hand. Rat's reproductive organ anatomy. The vagina is lined also to the urinary bladder.

It divides into two uterine horns. That extends towards the kidneys. The ovaries are connected to the uterine via oviducts.

Identification of uterine and endometrium. By using the bladder as a landmark, we can see the cervix. Follow the cervix, we can see the branch of left and the right uterine horn.

Switch to the two-dimensional view by select b mode. After we find uterus, we should choose measurement in the menu bar, and then click linear to start the measurement. We can measure antero-posterior diameter of each uterine horn and meet its maker agent.

Endometrium thickness is measured from echogenic border to echogenic border. Across the endometrial cavity on a satch-al-mid-lie image. Use color doppler.

We can see the blood flow of uterine and endometrium. Results one from 28 rats. We got the antero-posterior uterine horn diameters.

And endometrium thickness in each uterine horn. There are no significant differences between two sides of the horn. Uterine artery blood flow of non-pregnant rats.

Here is the pentameter of the doppler mode. Care should be taken to align the blood flow and doppler beam to minimize the doppler angle. Doppler waveforms were obtained in the uterine artery.

Near the lateral inferior margin of the uretal cervical junction. Close to the een-eck artery on each side. Here are the results of the doppler studies in both sides of the uterine artery blood flow of non-pregnant rats.

We find there are no significant differences between different sides. Uterine artery blood flow of pregnant rats. This is the waveform of 13 days of pregnancy.

This is the waveform of 15 days of pregnancy. When rats get pregnant, it is much easier to find the uterine artery to compare the differences between the different stages of the pregnancy. As gestational advanced, peak systolic velocity and an-stie-er-staw-lick velocity increases significantly.

And a calculated resistance index decreases significantly in pregnant rats. Identification of ovary. Ovaries are located lateral to the kidneys on both sides of the rats.

And reside in fat pads found at the end of uterine horn. We can search from uterine to find ovary. Because the ovary are at the end of uterine horn.

And connected to the horn by fallopian tube. The green outlines defined external boundaries of the ovary and follicles. Here are the results of the main diameter of the ovary and periovulatory follicle size in each side.

There are no significant differences. Ovary artery blood flow. Color doppler modes and power doppler mode imaging, helps with identification of ovarian intensity.

And direction of flow. We also compared differences between different estrus cycle phase. Though the main endometrium thickness in estrus phase group is thicker than non-estrus phase group, no significant difference is shown in two groups.

By contrast, when we compared morphology of the endometrium, we find fluid in five rats need extra space. When we compared morphology of the ovary, we can find periovulatory follicles and fluid around ovary after ovulation. We also find that there are no significant differences of uterine artery blood flow between different estrus phases.

From the study, we could draw a conclusion that rat is a suitable model for the study of reproductive organ dynamics using transcutaneous ultrasound bio-microscopy. It will build a platform for doing further experiments by monitoring its sonographic change, without sacrificing animal.