Category Archives: Follicles - Part 2

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(7)

An objective lens of X40, a projective lens of X1.25, and a tube factor of X6.12 were used to obtain a final magnification of X306 on the video monitor. The position of the glass slide was fixed on the microscope stage, and each gray-scale image, consisting of 512 X 480 picture elements (pixels), was obtained for computer analysis by averaging 32 successive video frames from … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(6)

Slides were incubated overnight at 4°C with primary antiserum or follistatin-adsorbed primary antiserum. The next day, slides were incubated for 30 min with 1:400 dilution of biotinylated goat anti-rabbit IgG antibody (catalogue no. BA-1000; Vector Laboratories) prepared in 4% normal goat serum. The rest of the staining was carried out according to instructions provided in the Vectastain ABC kit. Slides were then dehydrated and coverslips … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(5)

Immunohistochemical Staining for Follistatin A pair of glass slides containing adjacent sections of tissue were incubated overnight with 1:1000 dilution of primary antiserum and follistatin-adsorbed primary antiserum (one slide each) to localize the follistatin and nonspecific reaction, respectively. The avidin-biotin peroxidase technique was used as described previously using a Vectastain ABC kit (Vector Laboratories, Burlingame, CA). Microscope slides of all follicles under study were stained … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(4)

On the basis of daily ultrasonographic records, follicles were identified as the dominant, largest subordinate, and second-largest subordinate on the day of ovariectomy. Regarding the dominant and largest subordinate follicles, only those that were individually identified were collected and analyzed. If on the day of ovariectomy the second-largest subordinate follicle could not be distinguished from other subordinates (i.e., similar diameter; D6W1, Da 17), one was … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(3)

Heifers were treated postoperatively with procaine penicillin G for 4 days. Immediately upon removal, the ovarian artery or its branches were cannulated, flushed with 15-20 ml PBS (0.1 M phosphate buffer, 0.9% sodium chloride, pH 7.27.4) to remove blood, and then perfused with 30 ml of Karnovsky’s fixative containing 4% paraformaldehyde and 0.1% glutaraldehyde in 0.1 M phosphate buffer (pH 7.4) at a flow rate … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(2)

Heifers in group Da 17 were ovariectomized 1 day after detection of proestrus; proestrus was defined as the day when any 3 of 4 estrus-like characteristics (i.e., high uterine tone, edematous echotexture, intrauterine fluid collection, mucous discharge) were detected. Days of ovariectomy were selected on the basis of previous studies to represent the growing (D3W1), early-static (D6W1), late-static (D1W2), and regressing (Da 17) phases of … Continue reading

Immunohistochemical Distribution of Follistatin: MATERIALS AND METHODS(1)

Animal Grouping and Ultrasonography The study was conducted on 16- to 18-mo-old sexually mature, nulliparous, crossbred beef heifers (primarily Hereford). Heifers (n = 27) were maintained in a single corral and fed to gain approximately 1.3 kg weight per day. Ovarian follicle development was monitored daily by transrectal ultrasonography using a 7.5-MHz linear-array transducer (Aloka Co. Ltd., Tokyo, Japan). Ultrasound examinations commenced at least 2 … Continue reading

Immunohistochemical Distribution of Follistatin in Dominant and Subordinate Follicles and the Corpus Luteum of Cattle(2)

The growth and atresia of individual antral bovine follicles have been monitored using sequential ultrasonography, and it has been established that growth of follicles > 4 mm takes place in 2 or 3 waves during the estrous cycle. Emergence of successive follicular waves during the estrous cycle was associated with increases in circulating concentrations of FSH that preceded wave emergence by 1 day. During an … Continue reading

Immunohistochemical Distribution of Follistatin in Dominant and Subordinate Follicles and the Corpus Luteum of Cattle(1)

Follistatin was first identified in bovine and porcine follicular fluid by its ability to suppress FSH secretion from pituitary cell cultures. Follistatin is a glycosylated single-chain protein that occurs in at least 6 forms ranging from 31- to 39-kDa molecular mass; smaller forms represent a carboxyl terminal truncation of the larger precursor. Although follistatin is known to be expressed in a number of tissues, a … Continue reading