Follicles In Group Research Articles

A monogamous pipefish has the same type of ovary as observed in monogamous seahorses

Syngnathid fish (pipefish and seahorses) are unique among teleost fish in that their ovary consists of a rolled sheet with germinal ridge(s) on the dorsal side running along the entire length of the sheet. A distinct difference is seen in the ovarian structure between polygamous Syngnathus pipefish and monogamous seahorses (Hippocampus spp.), the former having one germinal ridge and the latter with two ridges. This study examined the ovarian structure and the mode of egg production in a monogamous pipefish Corythoichthys haematopterus. The ovary of C. haematopterus had two germinal ridges like that observed in monogamous seahorses. There were two distinct groups of follicles in the ovary, one being a cohort of extremely small follicles and the other a cohort of follicles developing and increasing in size with the passage of time. We suggest that the ovarian structure and the mode of egg production in this pipefish are adaptations to monogamy.

OVARIAN APOPTOSIS AFTER SHOCK WAVE LITHOTRIPSY FOR DISTAL URETERAL STONES

The objective of this study is to identify any apoptotic effect of shock wave lithotripsy (SWL) for distal ureteral stones on ovarian tissue. Twenty-one female New Zealand White rabbits were divided into three groups of seven rabbits each: I (control), and II, III (treated and killed 14 and 28 days after SWL, respectively). The left distal ureteral segment of the anesthetized (ketamine HCl, 20 mg/kg) animals in groups II and III was exposed to 1,500 shock waves at 17 kV. Localization of the distal ureteral segments was achieved following contrast medium (Iohexol 300 mg of I/ml) injection. The animals were killed on day 14 or 28 after SWL, and the ovaries were removed. The follicle number with apoptotic changes in ovarian tissue was compared with control group. Apoptotic changes were determined by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) method. No increased apoptosis was detected in all groups. The mean number of TUNEL-positive follicle in groups I, II and III was 9.3 ± 2.9, 8.1 ± 2.6 and 8.7 ± 2.9, respectively. There were no statistically significant differences among all groups regarding the number of TUNEL-positive follicle (P = 0.647). Also, no histomorphological change other than apoptosis was detected in the study groups. In conclusion, SWL treatment for distal ureteral stones does not induce apoptotic changes on ovarian tissue.

Oocyte Morphometry in Female Dogs (Canis familiaris, Linnaeus, 1758)

In the present study, the ovaries of 15 healthy bitches divided into three groups according to age were analysed by histology and morphometry: group 1 (1-3 years), group 2 (>3-5 years) and group 3 (>5-7 years). After ovariosalpingohysterectomy, the ovaries were fixed, routinely processed for embedding in paraffin and stained with haematoxylin-eosin. The following morphometric parameters were analysed: maximum and minimum diameter (microm), perimeter (microm), area (microm(2)) and roundness of the cytoplasm and nucleus of oocytes from different types of follicles. Significant differences in the cytoplasmic and nuclear parameters of follicular oocytes between the experimental groups were determined by anova and the Tukey test (5%). For the biotechnology of reproduction, the present results showed that in vitro maturation yielded the best performance for oocytes from primordial follicles in group 3 females and for oocytes embedded in secondary and tertiary follicles in group 2 females. In addition, the present findings will help in the diagnosis and prognosis of diseases affecting bitches, and will especially contribute to a better understanding of these cells by researchers in the field of histology and canine reproduction.

Microarray analysis of gene expression in granulosal cells from persistent follicles in cattle

Granulosal cells form highly specialized membrane connections with the oocyte and each other, allowing the passage of regulatory molecules and metabolites between cells. Gene expression changes in granulosal cells may adversely affect oocyte competence resulting in early embryonic loss. The present study was conducted to analyze global gene expression profiles in granulosal cells from persistent ovarian follicles in cows. Cows were assigned randomly to two groups: growing follicles on day 8 and persistent follicles on day 15 of the estrous cycle (estrus = day 0). Cows in the persistent follicle group received progesterone from CIDR-B devices on days 4 through 13. Granulosal cells were collected from both growing and persistent follicles and used in a direct comparison microarray experiment using a bovine long oligo array representing ∼8400 known genes. Analysis of the microarray data revealed up-regulation of 272 genes ( M-value ≥ 0.9) and down-regulation of 203 genes ( M-value ≤ −0.9) in granulosal cells from persistent follicles in comparison to growing follicles. Grouping of these genes into themes revealed altered expression of many genes involved in energy and protein metabolism, amino acid transport and apoptosis in granulosal cells of persistent follicles. These data suggest that aged granulosal cells may have a reduced capacity to provide energy and amino acids to the oocyte.

Immunohistochemistry Differentiates Papillary Thyroid Carcinoma Arising in Ectopic Thyroid Tissue from Secondary Lymph Node Metastases

To verify whether immunohistochemistry might be useful in the distinction between a true laterocervical metastasis of an undetected thyroid carcinoma and a primary tumor outside the gland. Galectin-3, cytokeratin 19, and HBME-1 were assessed in six cases (group A) of laterocervical masses harboring papillary thyroid carcinoma (PTC) but without a thyroid tumor, and in eight cases (group B) showing PTC both in the thyroid and in the laterocervical masses. In both groups, normal-looking follicles adjacent to the laterocervical neoplasia were present. We found that the apparently normal follicles in group A were negative for all the antibodies, while group B showed strong and diffuse positive immunostaining. The neoplastic areas were always positive for all the antibodies in both groups. Even if immunohistochemical patterns of residual follicles of group B are very well differentiated that they resemble normal thyroid parenchyma, they may well be metastatic carcinomas. On the contrary, the presence of morphologically and immunohistochemically normal-looking follicles in group A, with no intrathyroid tumor, suggests that the primary PTC might possibly develop in the ectopic thyroid tissue. In cases showing morphologically and immunohistochemically normal-looking follicles in laterocervical masses, these findings might lead to a reduction of the overdiagnosis of metastatic disease of an undetected carcinoma.

EXPRESSION OF EXTRACELLULAR MATRIX DEGRADING PROTEASES AND VEGF IN FOLLICLES BEFORE AND AFTER GnRH APPLICATION AND AFTER OVULATION IN THE COW

There is evidence that extracellular matrix (ECM) proteases like matrix metalloproteases (MMP) and plasminogen activator (PA) as well as angiogenic factors VEGF are implicated in tissue remodeling during final follicle development and ovulation in the ovary. The objective of this study was to evaluate the expression pattern of MMP, PA and VEGF system members in time defined follicle classes before and after GnRH application and after ovulation in cow. We characterized in our study the mRNA patterns of the members of MMP (MMP-1, MMP-2, MMP-14, MMP-19, TIMP-1, TIMP-2), PA (tPA, uPA, uPAR, PAI-1) and VEGF family (VEGF-A Isoform 120, 164 and 188 and VEGFR-1 and VEGFR-2) after FSH follicle stimulation and GnRH induced ovulation. Ovaries containing preovulatory follicles or new corpora lutea (CL) were collected at 0, 4, 10, 20, 25 (follicles) and 60h (CL day 1–2) relative to injection of GnRH to induce an LH surge (n=5/group). The expression of MMP-1 mRNA increased rapidly (610-fold upregulation) 4h after GnRH injection (during LH surge) and remained high during the whole experimental period. The MMP-2, MMP-14 and TIMP-2 mRNA expression did not change throughout the experiment when compared with the time before GnRH application. In contrast MMP-19 mRNA expression did not change in follicle classes during periovulation but increased significantly only after ovulation (CL day 1–2). The TIMP-1 mRNA increased significantly 4h after GnRH application (during LH surge) in order to increase again after ovulation. From the PA family, tPA mRNA increased 4h after GnRH (during LH surge) and remained high during the whole experimental period. The uPA mRNA expression did not change in follicle classes during periovulation but increased significantly only after ovulation. The uPAR and PAI-1 mRNA expression increased in follicle group at 4h after GnRH application (during LH surge), in order to increase again after ovulation. The VEGF120 and VEGF164 mRNA decreased 20h after GnRH and periovulation phase. VEGF188 mRNA already decreased at 10h after GnRH followed by a further decline during periovulation. All VEGF isoform transcripts increased again after ovulation. The mRNA of both VEGF receptors decreased significantly during periovulation phase, followed by a significant increase in early CL. All VEGF isoforms are upregulated after ovulation suggesting an active participation in regulation of angiogenesis in early bovine CL. In conclusion, the temporal and spatial expression pattern of ECM proteases (MMP and PA systems) and VEGF during periovulation suggest them to be important mediators of LH dependent rupture of bovine follicle and early CL formation (angiogenesis). Supported by DFG, BE 3189/2–1. (poster)

Effect of vitrification method on survivability, follicular growth and ovulation of preantral follicles in mice

This study was designed to compare the survival rates, follicular growth rates, and ovulation rates of vitrified preantral follicles (PF) from ovaries with those isolated from a vitrified ovarian cortical strip. Mouse ovaries were divided into three groups: those not treated by vitrification of the PF (control), those treated by vitrification of the PF isolated from the ovaries (group I), and those treated by vitrification of ovarian tissue followed by PF isolation (group II). The group I samples were exposed to equilibration solution (EG-20) for 5.0 min plus vitrification solution (EFS-40) for 0.5 min, while the group II samples were exposed to EG-20 for 10.0 min plus EFS-40 for 2.0 min, before vitrification. They were subsequently placed on an electron microscope grid, and submerged immediately in liquid nitrogen. After thawing, the survival rate and the growth rate of the follicles were evaluated every 2 days. In the in vitro condition, the follicles grew and developed into antral follicles in groups I and II. The survival rate of the group I samples was higher than that of the group II samples during the in vitro culture (P<0.05). The growth rates of the follicles in group I were higher than those in group II after day 6 (P<0.05). The ovulation rate of the samples in group I was higher than that of group II (P<0.05). These results demonstrated that direct PF vitrification appeared to be better than vitrification of the PF isolated from ovarian tissue.

In-vitro Maturation of Immature Oocytes from Preantral Follicles in Prepuberal Mice

Objective To observe the morphological changes in in vitro growth of preantral follicle isolated from prepuberal mice and to assess impacts of gonadotropin (Gn), insulin transferrin selenium (ITS) and epidermal growth factor (EGF) on their development. Methods Early preantral mice follicles (90–130 μm diameter) were mechanical isolated and selected from 2 weeks old mice and then cultured in alpha-minimal essential medium (α-MEM) with or without Gn, ITS and EGF. The preantral follicles were cultured singly in 20 microliters droplets for up to 14 d. The medium was replaced and the follicles were observed everyday. Granulosa cells (GC) prolification, antrum formation and oocyte maturation were recorded. Results The medium with Gn supported preantral follicle culture in vitro, during which they retained a three-dimensional structure, maintained oocytes viability and increased in diameter and number of somatic cells. Preantral follicles cultured in Gn medium grew obviously, while those without Gn grew slowly and after 6 d's culture began to shrink and blacken. Significant increase in survival rate and maturation rate of oocytes was observed in Gn group (P Conclusions α-MEM can be the medium for in vitro culture (IVC) of preantral follicles, but need to be added with rLH/rFSH, rHCG/rEGF to facilitate thecal cell attachment, GC proliferation and oocyte maturation.

Determining the daily spawning cycle of the chokka squid, Loligo reynaudii off the South African Coast

The study investigated the duration and peak of the daily spawning cycle of the chokka squid Loligo reynaudii, and the possibility of estimating the spawning frequency by means of classification and grouping (by age) of post-ovulatory follicles. Post-ovulatory follicles were classified into three types: new, intermediate or old, based in part on the degree of resorption of the follicles determined from histological sections. Ovulation in this species appears to be a rapid process, seen by the occurrence of both mature oocytes and post-ovulatory follicles in partially spent ovaries. Results suggest that chokka squid present a diel timing of spawning, with successive periods of egg accumulation at night, interrupted by periods of active spawning during the day. The ovarian cycle for this species appears typical of serial spawners. During the spawning phase ovaries go through ripe, partially spent and recovering stages by undergoing a process of maturation, ovulation and redeveloping, where a new batch of advanced oocytes is recruited. The cycle typically appears to last between 24 and 36 h, and may depend on a number of factors such as environmental conditions and the presence of predators. The short-lived (about 14 h) nature of the post-ovulatory follicles precludes the calculation of the exact spawning interval and does not allow us to accurately predict the spawning frequency. Together with the degree of oviduct fullness they do however give a good indication of imminent or recent spawning.

Follicle Size-Dependent Changes in Follicular Fluid Components and Oocyte Diameter in Antarctic Minke Whales (Balaenoptera bonaerensis)

The concentrations of various components of follicular fluid were compared among three groups of follicles (small, <5 mm; medium: 5-10 mm; large, >10 mm) with a control that consisted of the components of umbilical serum using seven pregnant Antarctic minke whales. Follicular oocytes recovered from the follicles were also used for measurement of oocyte diameter after removing the cumulus cells. The mean diameter of the ooplasm in the oocytes from the large follicles (143.2 microm) was significantly greater than those from the small (127.1 microm) and medium (131.7 microm) follicles, although there were no significant differences in diameter of the whole oocyte and thickness of the zona pellucida among the three follicular sizes. The osmolarity of the follicular fluid from the small follicles (363.3 mOsmol) was significantly lower than that of the medium follicles (388.9 mOsmol) and tended to be lower than that of large (381.9 mOsmol) follicles, respectively, both of which were similar to that of the umbilical serum (379.5 mOsmol). There was no significant difference in the concentrations of all components of the follicular fluid between the medium and large follicles. As compared with the values of the umbilical serum, the total-protein, glucose, albumin and chlorine concentrations of the follicular fluid from the medium and large follicles were significantly higher, and the total cholesterol and calcium concentrations were significantly lower. The concentrations of lactic acid (85.3-136.0 mg/dl) of the follicular fluid from the three groups of follicles were significantly lower than that of the umbilical serum (360.0 mg/dl). Among the follicles, the follicular fluid from the small follicles (136.0 mg/dl) contained a significantly higher concentration of lactic acid than that from the large follicles (85.3 mg/dl). The progesterone concentrations were not significantly different among the fluid from the three group of follicles and the umbilical serum: however, the estradiol 17-beta concentrations of the follicular fluid increased with the size of the follicle (14.3 and 34.6 ng/ml for small and large follicles, respectively). These results offer new information concerning whale reproductive physiology, especially for improvement of in vitro oocyte maturation and related technologies in whales.

Reproductive endocrine profiles and follicular growth after estrus induction in the riverine water buffalo (Bubalus bubalis, 2n=50) and riverine-swamp hybrid buffalo (2n = 49)

Ten adult female water buffalo were used in the present study (5 x [2n = 50] and 5 x [2n= 49] hybrids). Ovarian activity was monitored daily by transrectal ultrasonography between two consecutive ovulations. Observed follicular wave numbers were: 1 (n=1), 2 (n=4), and 3 (n=5). The interovulatory interval ranged 17 to 23 days. Differences in mean follicular diameter between follicles of the normal karyotype (2n=50) and buffalo hybrids (2n=49) were found on the second subordinate group of follicles (P<0.05) but not between dominant and third subordinates. Differences in circulating concentrations of P4 and estradiol were not statistically significant (P>0.05), whereas inhibin profiles were significantly higher in the hybrid group (P<0.05). Understanding the biological meaning of the difference in inhibin concentrations in B. bubalis female reproductive performance will require further investigation.

250 CYTOPLASMIC DYNEIN INTERMEDIATE CHAIN AND DYNACTIN p150Glued EXHIBIT DISTINCT SPATIAL AND TEMPORAL MICROTUBULE ASSOCIATIONS DURING BOVINE IN VITRO MATURATION AND ARE AFFECTED BY FOLLICLE SIZE

Microtubule molecular motors are critically involved in transporting vesicles during interphase, in building and maintaining spindles during mitosis and meiosis, and also in the localization of various organelles. DYNC1I1 (cytoplasmic dynein 1 intermediate chain) and its cofactor DCTN1 (dynactin p150Glued) are crucial for oocyte maturation but their role during mammalian female meiosis is not yet known. The goal of this study was to analyze the dynamics of these proteins in oocytes collected from different-size follicles at different stages of in vitro maturation (IVM), i.e., germinal vesicle stage (GV), germinal vesicle breakdown (GVBD), metaphase I (MI), and metaphase II (MII), and their association with microtubules. Ovaries were collected at a local abattoir. Cumulus–oocyte complexes (COCs) were aspirated from follicles either &lt;2 mm or 2–8 mm in size and matured in M199, supplemented with 1% fatty acid-free BSA, 10 UI pregnant mare serum gonadotropin (PMSG)/5 UI HCG, and 100 µm cysteamine, at 39�C and 5% CO2. Follicle sizes and time points for fixation were: GV-0 h; GVBD-8 h for oocytes &lt;2 mm and 9 h for oocytes 2–8 mm; MI-15 h; MII-24 h (Racedo et al. 2007, pub. online: 10.1002/mrd.20770). The distribution of the proteins was assessed by immunocytochemistry and laser confocal microscopy. The attached cumulus cells and zona pellucida of oocytes were removed in TALP-HEPES medium containing 1 mg mL–1 hyaluronidase and 2 mg mL–1 pronase, respectively. The oocytes were then incubated in a fixation–permeabilization solution containing 2% formaldehyde and 0.1%Triton X-100 for 1 h. Samples were then blocked for 1 h in 10 mm PBS + 0.3% BSA + 1% fetal calf serum (ICC blocking solution). The primary antibody was applied over night at 4�C, followed by treatment with fluorochrome-conjugated secondary antibodies for 1 h at 37�C in the dark. After RNase treatment, oocytes were incubated with TOTO-3 (Invitrogen, Carlsbad, CA, USA) to visualize the DNA. The material was mounted in an anti-fade medium (Vectashield�, Vector Laboratories, Burlingame, CA, USA) and imaged with a Zeiss laser scanning microscope. Immediately after chromatin condensation (GVBD), dynactin was in close association with the DNA and interacting with the spindles in MI and MII oocytes recovered from large follicles. No clear association with the DNA was observed in GVBD oocytes obtained from small follicles; little dynactin was found in MI and MII spindles. Dynein localization did not differ from dynactin in GVs and was homogeneously distributed in the cytoplasm of both groups of follicles. Dynein was not associated with the DNA in the GVBD stage while at MI and MII it was associated with the meiotic spindle. The association of dynein with microtubules was weak at the MI stage in oocytes from small follicles. Results provide insight into the regulatory mechanisms of oocyte maturation and a possible relationship with oocyte competence.

Dissociation of oocyte nuclear and cytoplasmic maturation by the addition of insulin in cultured bovine antral follicles

Follicles of 4-8 mm in diameter were dissected from ovaries and cultured in Waymouth culture medium in the presence or absence of insulin (5 mug/ml) at 39 degrees C in a humidified atmosphere of 45% O2, 5% CO2 and 50% N2 for 24 h. Following follicle culture, the oocytes were collected and examined for developmental potential, total protein profile and ultrastructural aspects. Oocytes aspirated directly from follicles of the same size were used as controls. Addition of insulin to the follicle culture medium significantly reduced expression of the low molecular weight insulin-like growth factor-binding proteins (IGFBPs) in the follicular fluid, and significantly reduced the cleavage rate of subsequently matured and fertilised oocytes (0.52 vs 0.61). However, there were no differences in the proportion of cleaved embryos which developed to the blastocyst stage (0.30 vs 0.28), nor embryo quality as assessed by total cell number (137 +/- 8.53 vs 124.6 +/- 6.95). The total protein profiles of immature oocytes recovered after 24 h of follicle culture were compared by PAGE. There were marked differences between the two groups, unmatured oocytes recovered from the insulin-positive follicle group showed a protein pattern similar to that of matured oocytes. In addition, examination of ultrastructural features by transmission electron microscopy indicated that oocytes from follicles cultured in the presence of insulin undergo many of the cytoplasmic changes associated with oocyte maturation. In conclusion, follicle culture in the presence of insulin is beneficial for follicular survival and significantly reduces cleavage but has no detrimental effects on the development of cultured embryos. However, many of the cytoplasmic changes associated with oocyte maturation occur prior to the induction of nuclear maturation.

Changes in fibroblast growth factor 2 and its receptors in bovine follicles before and after GnRH application and after ovulation

The aim of this study was to evaluate the expression pattern of fibroblast growth factor 2 (FGF2), its receptor variants (FGFR1IIIc, FGFR2IIIc) and nucleolin in time-defined follicle classes before and after GnRH application and after ovulation in the cow. Ovaries containing preovulatory follicles or new corpora lutea (CL) were collected at approximately 0, 4, 10, 20 and 25 h (follicles) and 60 h (new CL) relative to injection of GnRH to induce an LH surge (n = 5 animals per group). The expressions of FGF2 and FGFR1IIIc mRNA were significantly up-regulated only in the follicle group 4 h after GnRH (during the LH surge) with a significant down-regulation immediately afterwards. Western blot analyses showed two protein bands with at 22 and 18 kDa with apparent up-regulation beginning with the LH surge (4 h) and maximum levels 20 h after GnRH. FGF2 protein in follicles collected at 0 h (before LH surge) was localised in theca tissue (endothelial and pericytes of blood vessels) but not in granulosa cells (GCs). The FGF2 staining (by immunohistochemistry) pattern changed dramatically after the LH surge for a short period (about 2 days) and FGF2 protein was localised dominantly in the nucleus of many GCs, while most capillary endothelial cells were FGF2 immunonegative. In conclusion, the novel observation of FGF2 up-regulation and the distinct change in FGF2 localisation from theca (cytoplasm of endothelial cells) to the nucleus of GCs after the LH surge may be important for survival of GCs or for the transition of the GCs to luteal cells.

Expression of Fibroblast Growth Factor 1 (FGF1) and FGF7 in Mature Follicles during the Periovulatory Period after GnRH in the Cow

The aim of this study was to evaluate the expression pattern of mRNA for fibroblast growth factor 1 (FGF1), FGF7, and their receptor variants (FGFR2IIIb) in time-defined follicle classes before LH surge, between LH surge and ovulation, and in the early corpus luteum (CL) in the cow. The ovaries were collected by transvaginal ovariectomy (n=5 cows/group), and the follicles (n=5, one follicle/cow) were classified into the following groups: before GnRH administration (before LH surge); 3-5 h after GnRH (during LH surge); 10 h after GnRH; 20 h after GnRH; 25 h after GnRH (periovulation), and early CL (Days 2-3). The mRNA expression was analyzed by quantitative real-time PCR (RotorGene 3000). The mRNA expression of FGF1 showed no significant differences in the follicle groups examined, but increased significantly at the early CL phase. A transient increase in FGF7 mRNA expression was observed 3-5 h after GnRH and again in the early CL phase. In contrast, the expression of FGFR2IIIb was constant throughout the period from the final growth of the follicle to early CL formation. The results of this study suggest that FGF1 and FGF7 may be involved differently in the process of follicle maturation and CL formation, which is strongly dependent on angiogenesis.

359 ICSI AND ACTIVATION OF OOCYTES RECOVERED FROM TRANSITIONAL AND CYCLING MARES

Ovarian follicular development in mares during the transitional period before the breeding season leads to an accumulation of antral follicles of various sizes. The quality of oocytes at this stage may be compromized until the first seasonal ovulation. In this study, we evaluated the developmental competence of oocytes recovered from transitional and cyclic mares, and the effect of zygote activation after intracytoplasmic sperm injection (ICSI). A 2 × 2 × 2 factorial experiment consisting of oocytes from transitional and cyclic mares, two follicle sizes (10 to 20 and 20+ mm), and two treatments (control and activated) was conducted. Follicular oocytes of 14 mares were aspirated in March and April (transitional) and May to July (cyclic) five times per each period at 10-day intervals, without use of hCG. Oocytes aspirated from mares were matured in vitro in a defined medium similar to SOF plus FSH, LH, epidermal growth factor (EGF), insulin-like growth factor (IGF), estradiol (E2), prostaglandin (P4) and 10% FCS, for 30 ± 1 h under 5% CO2 in air at 38.5°C; oocytes with a first polar body were used for ICSI. Motile sperm from frozen-thawed semen were used for sperm injection with a piezo-driven pipet. For activation after ICSI, presumptive zygotes were cultured in G1.3 containing 0.02 µM phorbol 12-myristate 13-acetate (PMA) for 2 h, and then in 2 mM 6-dimethylaminopurine (6-DMAP) for 3 h under 6% CO2 in air at 38.5°C. Zygotes were cultured in 50 µL drops of DMEM/F12 containing 10% FCS for 9 days at 38.5°C in 5% CO2/5% O2/90% N2. Medium was replaced every 3 days. Cleavage and blastocyst rates were calculated based on non-degenerating injected oocytes. Data were analyzed by Fisher's exact test. A total of 115 and 78 oocytes were recovered from cyclic and transitional mares. Average maturation rates to MII in the respective groups were 76.5 and 65.4%, respectively (P &lt; 0.07), and those of 10 to 20 and 20+ mm follicle groups were 70.6 and 80.0%, respectively (P &gt; 0.05). The average cleavage rate in cyclic mares was higher than in transitional mares, and that of the activated group averaged over follicle sizes was higher than that of controls (P &lt; 0.05; Table 1); those of 10 to 20 and 20+ mm follicle groups were not different (P &lt; 0.05; Table 1). Blastocyst rates per oocyte within main effects were not different (P &lt; 0.05; Table 1). Oocytes from transitional mares had lower cleavage rates than those of cyclic mares, but blastocyst development was similar. Activation of zygotes clearly improved cleavage rates of in vivo-derived immature equine oocytes after ICSI. Table 1. Main effect means of responses after ICSI

Effect of the Dominant Follicle Aspiration before or after Luteinizing Hormone Surge on the Corpus Luteum Formation in the Cow

Luteinizing hormone (LH) surge and follicle rupture act as trigger to start corpus luteum (CL) formation. Thus, we aimed to investigate whether a dominant follicle that has not been exposed to an LH surge can become a functional CL. For this purpose, follicular fluid from the dominant follicles (DF) of cows was aspirated before or after a GnRH-induced LH surge, and subsequent CL formation was observed. Holstein cows were divided into four groups as follows: Luteal phase, a DF was aspirated 7 days after GnRH injection; Pre-LH surge, a DF was aspirated 42 h after PGF(2alpha) injection during the mid luteal phase; Post-LH surge, a DF was aspirated 24 h after GnRH injection following PGF(2alpha); and Intact follicle, ovulation was induced by GnRH injection after PGF(2alpha). Observation of morphological changes in the aspirated follicle using color Doppler ultrasonography and blood sampling was performed on Days 0, 3, 6, and 9 (Day 0 = follicle aspiration). CL formation following DF aspiration was observed only in the Post-LH surge group. In both the Luteal phase and Pre-LH surge groups, however, none of the cows showed local blood flow at the aspirated site or CL formation. Luteal blood flow area, CL volume, and plasma progesterone concentration in the Post-LH surge group were no different from those in the Intact follicle group. The present results clearly demonstrate that rather than follicle rupture, it is the LH surge that is essential for CL formation in cows.

Effects of isolating methods (mechanical or enzymatical) on structure of pre-antral follicles in mouse

This study was conducted to evaluate the stable and effective isolating method of pre-antral follicles from ovary by means of mechanical or enzymatical method in mice. Mouse (ICR, 3-4 weeks old) ovarian pre-antral follicles of 70-130 microm (A: < or = 90; B: 91-110; C: 111-130 microm) in diameter were isolated by mechanical method (group I) using syringe needles or by enzymatical method (group II) using 600 IU collagenase and DNase and cultured individually in 20 microL droplet of media under mineral oil on culture dish for 8 days. On 8th day after culture, disruption rate (84.4 +/- 18.8% vs. 9.4 +/- 18.8%) was significantly higher (p < 0.05) in group II than in group I. Survival rate (88.0 +/- 28.9% vs. 0%) was significantly higher (p < 0.0000) in group I than in group II. There were no differences in the survival rate among different initial sized pre-antral follicles in group I (A: 86.7 +/- 12.5%, B: 100%, C: 69.2 +/- 30.0%, NS) or group II (A: 0%, B: 0%, C: 0%, NS), respectively. In conclusion, compared to mechanical dissection, enzymatical isolation of pre-antral follicles resulted in higher follicular disruption rate. Survival rate was not affected by different initial sizes of pre-antral follicles in mice.

Apoptosis in cryopreserved human ovarian tissue obtained from cancer patients: A tool for evaluating cryopreservation utility

Fertility preservation is of major importance for women with cancer in whom ovarian function may be disturbed by the use of potentially sterilizing chemotherapeutic drugs and/or pelvic irradiation. Cryopreservation of ovarian cortical tissue is one of the potential options for preserving fertility among these women. Cryopreserved thawed human ovarian tissue can be autografted either orthotopically or heterotopically, but may also be transplanted first into an animal host with subsequent maturation and collection of oocytes. The objective of this study was to investigate the prevalence of ovarian follicular apoptosis in fresh and frozen/ thawed human ovarian tissue as a measure of follicular viability. The study group included 6 women with cancer who underwent ovarian tissue cryopreservation (OTCP). Ovarian tissue samples (n = 2) were obtained from each woman with one sample undergoing evaluation for apoptosis immediately following removal (control, group A) and the other evaluated for apoptosis following freezing/thawing (group B). Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) and 4'6' diamido-2-phenylindole hydrochloride (DAPI) staining methods were used to investigate follicular apoptosis. Morphological changes in the same samples were evaluated in hematoxylin and eosin (H&E)-stained sections. In each slide, only primordial and primary follicles were evaluated for abnormal morphology and apoptosis. Abnormal morphology was demonstrated in 23.8+/-8.7% of group A follicles compared to 48.3+/-11.2% of group B follicles (p < 0.05). Apoptosis was demonstrated in 25.4+/-8.4% of group A follicles compared to 60.9+/-6.0% of group B follicles (p < 0.05). We have shown that the ovarian follicles in group B demonstrated a higher incidence of apoptosis compared to those of group A. Therefore, the data suggest that follicular apoptosis might be a consequence of the freezing and thawing procedure. This may be used as a method for evaluating and comparing the outcome of different freezing/thawing protocols.

Ovarian follicular and luteal dynamics in wapiti during the estrous cycle

The reproductive tracts of 13 mature hinds were examined daily by transrectal ultrasonography and blood samples were taken daily from October to January to characterize follicular, luteal, and endocrine dynamics in wapiti during the estrous season. Follicle development occurred in waves characterized by regular, synchronous development of a group of follicles in temporal succession to a surge in serum FSH concentration. The mean interovulatory interval was 21.3 ± 0.1 d, but was shorter in hinds exhibiting two follicular waves than in hinds exhibiting three and four waves ( P < 0.05). The interwave interval was similar among waves in two-wave cycles and the first wave of three-wave cycles. All other interwave intervals in three- and four-wave cycles were shorter ( P < 0.05). The maximum diameter of the dominant follicle of the first wave was similar among two-, three-, and four-wave cycles. For all other waves in three- and four-wave cycles, the maximum diameter was smaller ( P < 0.05). Corpus luteum diameter and plasma progesterone concentrations were similar between two- and three-wave cycles, but the luteal phase was longer ( P < 0.05) in four-wave cycles. The dominant follicle emerged at a diameter of 4 mm at 0.4 ± 0.1 and 0.8 ± 0.1 d before the largest and second largest subordinate follicles, respectively. The follicle destined to become dominant was larger ( P < 0.05) than the largest subordinate follicle one day after emergence, which coincided with the first significant decrease in serum FSH concentration. We concluded that the estrous cycle in wapiti is characterized by two, three, or four waves of follicular development (each preceded by a surge in circulating FSH), that there is a positive relationship between the number of waves and the duration of the cycle, and an inverse relationship between the number of waves and the magnitude of follicular dominance (diameter and duration of the dominant follicle).