Impaired ovarian blood flow and reduced antral follicle count following laparoscopic salpingectomy for ectopic pregnancy

BACKGROUND: Whether salpingectomy affects ovarian function is controversial. In this study, ovarian function was assessed by antral follicle count, ovarian volume and ovarian stromal blood flow measured by three-dimensional (3D) power Doppler ultrasonography. The objectives of the study were to compare the ovarian function of the operated side with the non-operated side after unilateral salpingectomy performed through laparoscopy or laparotomy for ectopic pregnancy. METHODS: Thirty-two patients with unilateral salpingectomy performed for ectopic pregnancy were recruited: 18 through laparoscopy and 14 through laparotomy. Ultrasound scans were performed in the early follicular phase. RESULTS: Ovarian volume, antral follicle count and 3D power Doppler indices were comparable between the operated and the non-operated sides in the whole group and in the laparotomy group. The antral follicle count and 3D power Doppler indices were significantly reduced on the operated side in the laparoscopy group. CONCLUSIONS: Ovarian function seems to be impaired after laparoscopic unilateral salpingectomy at short-term assessment.     

Effects of oral contraceptive, synthetic progestogen or natural estrogen pre-treatments on the hormonal profile and the antral follicle cohort before GnRH antagonist protocol

BACKGROUND: Steroid pre-treatments may be useful to program GnRH antagonist IVF/ICSI cycles. This prospective study assessed hormonal and ultrasound data collected during the free period after the discontinuation of three different pre-treatments to provide information on the optimal time interval required before starting stimulation. METHODS: Women were randomized to receive oral contraceptive pill (OCP) [ethinyl estradiol (E(2)) 30 microg + desogestrel 150 microg] (n = 21) or norethisterone 10 mg/day (n = 23) or 17-betaE(2) 4 mg/day (n = 25) or no pre-treatment (n = 24) for one cycle before IVF. Assessments were performed on post-treatment day (PD) 1, 3 and 5, or on spontaneous cycle day (CD) 1 and 3. RESULTS: After OCP and progestogen administration, FSH and LH concentrations shifted from strongly suppressed PD1 levels to PD5 values similar to those observed on CD1. Meanwhile, follicle sizes remained small up to PD5. In contrast, estrogen pre-treatment poorly reduced FSH levels on PD1 compared with OCP or progestogen. Consequently, follicle size was more heterogeneous. FSH rebound was maximal on PD3, whereas LH levels were slightly increased up to PD5. CONCLUSIONS: A 5-day free interval after OCP or progestogen offers the advantages of gonadotrophin recovery and homogeneous follicular cohort, whereas early FSH rebound occurring after estrogen pre-treatment argues for a short free period.     

Early ultrastructural changes of antral mucosa with aspirin in the absence of Helicobacter pylori.

AIMS--To describe the ultrastructural changes that occur in human antral mucosa following direct application of aspirin in volunteers without Helicobacter pylori infection. METHODS--Ten healthy male volunteers without H pylori infection underwent three consecutive endoscopies (at zero, one and five hours). At the first endoscopy, two biopsy specimens were obtained (one for histology and the other for electron microscopy (EM)). At subsequent endoscopies, a single biopsy specimen was obtained for EM. A 50 ml solution of aspirin (concentration 3 mg/ml) was applied to the antral mucosa at the first endoscopy in five subjects; the other five subjects received 50 ml distilled water (placebo). RESULTS--The ultrastructural appearance of the first biopsy specimen in all subjects and subsequent biopsy specimens in the placebo treated subjects was normal. The aspirin treated group had evidence of intercellular oedema, widening of capillary fenestrae, rupturing of apical membranes, and dilatation of endoplasmic reticulum and mitochondria after one hour; these changes were more marked at five hours. Tight junctions were maintained. CONCLUSION--This is the first study to describe the early ultrastructural changes in antral mucosa induced by aspirin in subjects without H pylori infection.     

Cell-to-cell communication in the ovarian follicle: developmental and hormonal regulation of the expression of connexin43

The extensively developed network of cell-to-cell communication in the ovarian follicle is generated by gap junctions. In addition to the transmission of nutrients from the follicular cells to the oocyte, junctional communication in the ovarian follicle mediates the transfer of cAMP, the regulatory signal that maintains the oocyte in meiotic arrest. Luteinizing hormone (LH) interrupts cell-to-cell communication within the ovarian follicle, leading to a decrease in intra-oocyte concentrations of cAMP followed by resumption of meiosis. The developmental and hormonal regulation of the ovarian gap junction protein connexin43 (Cx43) and gene expression throughout folliculogenesis is reviewed in this article. An age-dependent increase in the amount of the Cx43 protein that was accompanied by its phosphorylation in preovulatory follicles has been observed. This protein disappeared after ovulation. The changes in both the amount and phosphorylation state of Cx43 were mimicked by exogenous administration of hormones as follows. Pregnant mare serum gonadotrophin increased Cx43 protein expression with a concurrent induction of its phosphorylation while a further human chorionic gonadotrophin injection resulted in a significant decrease of the protein. Cx43 mRNA showed a similar pattern of expression. In-vitro analysis of isolated ovarian follicles revealed that short time exposure (10 min) to LH stimulates phosphorylation of Cx43 followed by its immediate dephosphorylation, while longer incubations (8 and 24 h) with this hormone result in elimination of the protein. A significant decrease in Cx43 mRNA concentration at 24 h of incubation with LH was observed in these follicles. These results suggest that: (i) the presence of the gap junction protein in the ovary is developmentally regulated; (ii) after sexual maturation, both the amount of the Cx43 ovarian gap junction protein and its phosphorylation state are subjected to regulation by gonadotrophins; (iii) the LH-induced gating mechanism of the gap junctions in rat ovarian follicles is comprised of two steps: the immediate response is represented by a change in the phosphorylation state of the Cx43 protein, and the later response is manifested by a reduction of Cx43 protein concentration, due to attenuation of its gene expression.     

Severe ovarian hyperstimulation syndrome following salvage of empty follicle syndrome.

We report a case of severe ovarian hyperstimulation syndrome (OHSS) following a rescue of empty follicle syndrome (EFS). This suggests that the risk of developing OHSS remains unaltered even in the presence of EFS. The case supports the possibility of obtaining oocytes that fertilize and cleave normally after a second dose of human chorionic gonadotrophin (HCG) and a repeat oocyte retrieval. It supports the suggestion that the follicles are not necessarily empty in EFS. It demonstrates further that OHSS cannot be prevented by aspiration of follicular fluid and patients with large numbers of follicles and EFS must be warned of this potential complication.     

Mucosal surface morphology and histological changes in the duodenum of the rat following administration of cysteamine.

Acute duodenal ulcer can be produced in the rat by subcutaneous or oral administration of cysteamine. Development of this ulcer on the intestinal mucosal surface was followed from precursory stages to perforation using low power semimacroscopical and conventional histological techniques. The process started in the epithelium of the apical parts of the villi where segments of surface epithelial cells exfoliated and the lamina propria seemed to retract. As the process continued the villi gradually became lower eventually forming an avillous surface. Subsequently defects in the epithelium, necrosis, inflammation of the lamina propria, and a localized ulcer developed.     

Cardiovascular and hormonal changes following haemorrhage in the anaesthetized Brattleboro rat with an extracorporeal circulation

An extracorporeal circulation technique was developed for use in rats to provide equilibrated blood samples for multiple hormone assays. The inclusion of the extracorporeal circulation did not significantly alter arterial blood pressure, cardiac output, heart rate or central venous pressure in either Brattleboro rats with hereditary diabetes insipidus (BDI) or normal rats of the parent Long Evans (LE) strain. Plasma adrenaline and noradrenaline levels did not alter in either BDI or LE rats following inclusion of the extracorporeal circulation but the vasopressin concentration rose significantly in the LE rats. The impaired recovery of the mean arterial blood pressure following haemorrhage in the BDI rats compared with normal LE animals was not further influenced by the inclusion of the extracorporeal circulation. Plasma vasopressin and adrenaline (but not nor-adrenaline) levels were significantly raised during, and after, haemorrhage in the LE rats while in the BDI rats only plasma adrenaline levels were significantly increased. These results show that the insertion of an extracorporeal circulation into an anaesthetized BDI or LE rat does not adversely affect the cardiovascular system despite the increase in baseline plasma vasopressin concentration in normal rats, and its subsequent removal provides an additional equilibrated blood sample for multiple hormone assay within the same animal. The increased release of both adrenaline and vasopressin (but not noradrenaline) after haemorrhage in the same animal is detected using this technique, and the importance of vasopressin to the normal recovery process confirmed.     

Changes in ovarian morphology and serum hormones in the rat after treatment with dehydroepiandrosterone.

This investigation was designed to study ovarian and hormonal changes in the rat after treatment with dehydroeplandrosterone (DHEA). We identified a heterogeneous experimental group of animals with respect to ovarian histology: group I, corpora lutea (Cls) + cysts; group II, CLs + no cysts; group III, no CLs + cysts; group IV, no CLs + no cysts. Histological sections of these ovaries showed healthy and atretic follicles in different stages of cytomorphosis and degeneration. The aforementioned histological groups were also heterogeneous according to their hormonal profiles. Serum androgens, estrogens, and prolactin concentrations are significantly increased in DHEA-treated animals as compared with controls. There was no significant difference in follicle stimulating hormone between rats with cysts and rats without cysts after DHEA treatment. After 20 days of DHEA treatment, rats with CLs have very high levels of luteinizing hormone. Luteinizing hormone and prolactin levels are significantly higher in rats with cysts than in rats without cysts after 10 days of DHEA treatment. As has been shown in this inquiry, androgens and estradiol levels in rats with cysts after DHEA treatment are higher than those in rats without cysts after DHEA treatment. Therefore, this study suggests that the ovarian cystic condition developed after DHEA treatment in rats, is associated with higher levels of circulating androgens, estradiol, and prolactin.     

Immunization against gonadotrophin-releasing hormone: histopathological and hormonal changes in the female rat.

Immunization of female rats against gonadotrophin-releasing hormone (GnRH) resulted in cessation of the oestrus cycles, undetectable serum gonadotrophin levels and a reduction of pituitary gonadotrophin stores and of hypothalamic content of GnRH. Immunization abolished the post-ovariectomy rise in serum levels and in pituitary content of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) without affecting prolactin levels. This suggests that GnRH is involved in the regulation of synthesis as well as the secretion of LH and FSH. Histopathological changes were found in the pituitary, ovaries and uterus of the immunized rats. A marked reduction in the number of gonadotrophs as well as a small decrease in the size of other cells was observed in the pituitaries of rats having high anti-GnRH titres. Rats immunized 5 weeks before castration showed a marked reduction in the number and in the size of castration cells. The ovaries exhibited various degrees of atrophy which were correlated with the anti-GnRH titres. Rats with high anti-GnRH titres revealed extensive atrophy of stromal cells with disappearance of large follicles and corpora lutea; ovaries of rats with low titres of antibodies exhibited small corpora lutea and larger follicles, some of which were cystic. Uteri of rats having high titres of anti-GnRH were severely atrophied with cystic glandular dilation. Uteri of rats with low anti-GnRH titres showed squamous-cell metaplasia and fibrosis of the endometrial stroma.     

Cytochemical and ultrastructural changes in the osteoclast-like giant cells of giant cell tumor of bone following bisphosphonate administration

Giant cell tumor of bone (GCT) is a local aggressive neoplasm of bone characterized by expansive osteolytic lesions at the epiphysis of long bones. Bisphosphonates have been used to prevent bone resorption in secondary osteolytic tumors because of their strong anti-osteoclastic action. The authors studied the apoptosis and ultrastructural changes induced in osteoclast-like giant cells of GCT, following treatment with the aminobisphosphonate pamidronate in 16 patients with GCT of bone. Transmission electron microscopy (TEM) was used to identify ultrastructural changes, indicative of apoptosis, in the cytoplasm and the nucleus of the giant cells. Significant changes were observed in tumor samples from all 16 patients. In the cytoplasm these changes were characterized by abundant large tubular vesicles containing a central electrodense core scattered through the cytoplasm. In addition, mitochondria in the sections from pamidronate-treated patients appeared to be edematous when compared with sections from untreated patients. Nuclear changes in the giants cells were characterized by the formation of dense chromatin material scattered throughout the nucleus. The TUNEL labeling assay indicated that the mean pretreatment apoptotic index of 7.8% increased to 53% following pamidronate treatment. This was statistically significant (p<.001) and correlated well with the ultrastructural changes noted on TEM. The formation of abundant tubular vesicles in giant cells following bisphosphonate treatment may reflect disturbed vesicular trafficking and may affect the bone resorbing activity of giant cells.     

Changes in ovarian morphology and serum hormones in the rat after treatment with dehydroepiandrosterone

This investigation was designed to study ovarian and hormonal changes in the after treatment with dehydroeplandrosterone (DHEA). We identified a heterogeneous experimental group of animals with respect to ovarian histology: group I, corpora lutea (Cls) + cysts; group II, CLs + no cysts; group III, no CLs + cysts; group IV, no CLs + no cysts. Histological sections of these ovaries showed healthy and atretic follicles in different stages of cytomorphosis and degeneration. The aforementioned histological groups were also heterogeneous according to their hormonal profiles. Serum androgens, estrogens, and prolactin concentrations are significantly increased in DHEA-treated animals as compared with controls. There was no significant difference in follicle stimulating hormone between the with cysts and rats without cysts after DHEA treatment. After 20 days of DHEA treatment, rats with CLs have very high levels of luteinizing hormone. Luteinizing hormone and prolactin levels are significantly higher in rats with cysts than in rats without cysts after 10 days of DHEA treatment. As has been shwon in this inquiry, androgens and estradiol levels in rats with cysts after DHEA treatment are higher than those in rats without cysts after DHEA treatment. Therefore, this study suggests that the ovarian cystic condition developed after DHEA treatment in rats, is associated with higher levels of circulating androgens, estradiol, and prolactin.     

Mitochondrial ultrastructural and molecular changes induced by zidovudine in rat hearts.

Zidovudine (azidothymidine (AZT)) inhibits human immunodeficiency virus replication, prolongs survival, and delays progression of acquired immune deficiency syndrome. We determined AZT-induced molecular and ultrastructural changes in the rat heart. Rats (3 per group) were given drinking water with or without AZT (0.2 to 1.0 mg/ml; 29 to 102 mg/kg/day). After 21, 35, or 49 days, hearts were glutaraldehyde-fixed by abdominal aortic perfusion, processed, and examined by transmission electron microscopy. In parallel, myocardial RNA was extracted from hearts (AZT dose: 1 mg/ml; 35 days) and subjected to Northern analysis using cDNA probes for: alpha c-actin, troponin C, mitochondrial creatine kinase and malate dehydrogenase, a portion of the mitochondrial genome containing cytochrome b coding region (pMM26), and glyceraldehyde-3-phosphate dehydrogenase. Results showed marked and widespread cardiac mitochondrial swelling with fractured and disrupted cristae after 35 days of 1 mg/ml AZT. After a 14-day recovery, these ultrastructural defects did not reverse. Changes were not present in myocardium after 21 days of AZT nor after 35 days of lower dose AZT (0.2 mg/ml). Mitochondrial cytochrome b mRNA expression was depressed in AZT-treated rat hearts (35 days; 1 mg/ml AZT). mRNAs encoding glyceraldehyde-3-phosphate dehydrogenase, alpha c-actin, troponin C, mitochondrial creatine kinase, malate dehydrogenase, and mitochondrial ribosomal RNAs remained unchanged. AZT disrupts cardiac mitochondrial ultrastructure and expression of mitochondrial cytochrome b mRNA in a dose- and time-dependent fashion. The mechanism of AZT cardiotoxicity may relate to inhibition of mitochondrial DNA replication (at the level of DNA polymerase gamma) as postulated by others.     

The cone electrode: ultrastructural studies following long-term recording in rat and monkey cortex.

The achievement of long-term recording of neural signals from the central nervous system has potential clinical and investigative application. To facilitate long-term recording, a novel cone electrode composed of an insulated gold wire within a hollow glass cone had been developed. Cone electrodes containing sciatic nerve or neurotrophic medium were implanted into cerebral cortex in rats and monkeys. Electrophysiologic recordings had been previously obtained from cone tissue for as long as 15 months following implantation and this tissue contained silver-positive processes. We now extend these observations to characterize the fine structural features of the tissue within these long-term implants. Electron microscopy revealed central myelinated axons, dendrites, synaptic profiles, blood vessels, and glia; peripheral nerve was not found in the cones in which sciatic nerve had been placed. These observations further suggest ingrowth of cortical neurites and elements into the hollow glass tip of the cone and support the feasibility of long-term recording using this electrode.     

Changes in electrical properties of rat myometrium during gestation and following hormonal treatments.

1. The membrane properties of the rat myometrium, during gestation and following ovarian hormone treatment, have been investigated with the micro-electrode technique. 2. Spontaneously generated bursts of electrical activity alternating with silent periods were recorded from non-pregnant, pregnant and post-partum myometria. The membrane potential was highest during the middle stage of gestation, but the spike amplitude within a burst was not uniform. In the final stage of gestation and during parturition, the membrane potential was low and the spikes within a burst were of low frequency and uniform amplitude. 3. During parturition and post-partum, a gradual depolarization of the membrane, accompanied by an increase in membrane resistance, occurred before the generation of a burst. 4. Excitability of the membrane fluctuated from a peak just before the generation of a burst to a low after the cessation of a burst. 5. Displacement of the membrane potential by electrical current or by lowering the temperature modified the slope spontaneous depolarization, but the fluctuations of excitability persisted. The Q10 value for the frequency of spontaneous bursts, measured between 36 and 30 degrees C, was 3-8. 6. Hyperpolarization of the membrane increased the maximum rate of rise of the spike, but beyond -70 mV, the rate of rise was reduced. Half-inactivation of spike generation of spike generation occurred at a membrane potential less negative than the interburst potential, indicating that the current carrying system was not fully activated during parturition. 7. In both normal and spayed rats, oestradiol hyperpolarized the membrane and the burst of spikes was generated hyperpolarized the membrane and the burst of spikes was generated on a sustained depolarization. Progesterone slightly hyperpolarized the membrane and burst discharges occurred without a sustained depolarization. Simultaneous treatment with progesterone and oestradiol produced a plateau potential of long duration during burst discharges. 8. The thickness of the muscle layer, length constant of the tissue and time constant of the membrane were measured during gestation and from spayed rats under various hormonal conditions. The length constant of the tissue was increased by oestradiol and was further increased by simultaneous treatment withoestradiol and progesterone. The increase in tissue thickness appeared to have the most marked influence on the length constant. 9. The resting and active membrane properties of the progresterone treated myometrium were similar to those observed during the middle stages of gestation. The oestradiol-treated myometrium did not resemble that during the last stages of gestation and parturition, which was simulated by combination of the two hormones, oestradiol preceding progesterone.