The Experts below are selected from a list of 4656 Experts worldwide ranked by ideXlab platform
Angela B. Lange - One of the best experts on this subject based on the ideXlab platform.
-
myoinhibitors controlling oviduct contraction within the female blood gorging insect rhodnius prolixus
General and Comparative Endocrinology, 2015Co-Authors: Laura Sedra, Amir Haddad, Angela B. LangeAbstract:Abstract Muscle activity can be regulated by stimulatory and inhibitory neuropeptides allowing for contraction and relaxation. There are various families of neuropeptides that can be classified as inhibitors of insect muscle contraction. This study focuses on Rhodnius prolixus and three neuropeptide families that have been shown to be myoinhibitors in insects: A-type allatostatins, myoinhibiting peptides (B-type allatostatins) and myosuppressins. FGLa/AST-like immunoreactive axons and blebs were found on the anterior of the dorsal vessel and on the abdominal nerves. FGLa/AST-like immunoreactive axons were also seen in the trunk nerves and on the bursa. The effects of RhoprAST-2 (FGLa/AST or A-type allatostatins) and RhoprMIP-4 (MIP/AST or B-type allatostatins) were similar, producing dose-dependent inhibition of R. prolixus spontaneous oviduct contractions with a maximum of 70% inhibition and an EC 50 at approximately 10 −8 M. The myosuppressin of R. prolixus (RhoprMS) has an unusual FMRFamide C -terminal motif (pQDIDHVFMRFa) as compared to myosuppressins from other insects. Quantitative PCR results show that the RhoprMS receptor transcript is present in adult female Oviducts; however, RhoprMS does not have an inhibitory effect on R. prolixus oviduct contractions, but does have a dose-dependent inhibitory effect on the spontaneous contraction of Locusta migratoria Oviducts. SchistoFLRFamide, the myosuppressin of Schistocerca gregaria and L. migratoria , also does not inhibit R. prolixus oviduct contractions. This implies that FGLa/ASTs and MIP/ASTs may play a role in regulating egg movement within the Oviducts, and that the myosuppressin although myoinhibitory on other muscles in R. prolixus , does not inhibit the contractions of R. prolixus Oviducts and may play another role in the reproductive system.
-
octopamine modulates a central pattern generator associated with egg laying in the locust locusta migratoria
Journal of Insect Physiology, 2014Co-Authors: Raymond Wong, Angela B. LangeAbstract:Egg-laying in Locusta migratoria involves the control of a variety of complex behavioural patterns including those that regulate digging of the oviposition hole and retention of eggs during digging. These two behavioural patterns are under the control of central pattern generators (CPGs). The digging and egg-retention CPGs are coordinated and integrated with overlapping locations of neural substrate within the VIIth and VIIIth abdominal ganglia of the central nervous system (CNS). In fact, the egg-retention CPG of the VIIth abdominal ganglion is involved in both egg-retention and protraction of the abdomen during digging. The biogenic amine, octopamine, has peripheral effects on oviduct muscle, relaxing basal tension of the lateral and upper common oviduct and enabling egg passage. Here we show that octopamine also modulates the pattern of the egg-retention CPG by altering the motor pattern that controls the external ventral protractor of the VIIth abdominal segment. There is no change in the motor pattern that goes to the Oviducts. Octopamine decreased the frequency of the largest amplitude action potential and decreased burst duration while leading to an increase in cycle duration and interburst interval. The effects of octopamine were greatly reduced in the presence of the α-adrenergic blocker, phentolamine, indicating that the action of octopamine was via a receptor. Thus, octopamine orchestrates events that can lead to oviposition, centrally inhibiting the digging behavior and peripherally relaxing the lateral and common Oviducts to enable egg-laying.
-
the female reproductive system and control of oviposition in locusta migratoria migratorioides
Canadian Journal of Zoology, 2009Co-Authors: Angela B. LangeAbstract:The spermatheca acts as a repository for sperm deposited by the male and, in the African migratory locust (Locusta migratoria migratorioides (Fairmaire and Reiche, 1849)), is situated dorsal to the lateral and common Oviducts. In the locust, eggs mature in the ovaries and are ovulated into the lateral Oviducts where they are held until a suitable oviposition site is found. At that time, a hole is dug in the soil by the locust and, aided by muscular contractions of the upper lateral Oviducts, the eggs are propelled through the common oviduct and genital chamber and deposited in a pod in the soil. Contractions of the spermathecal sac lead to sperm release, resulting in fertilization of eggs in the genital chamber. Coordination of digging and of the Oviducts and spermatheca is clearly critical to the production of viable eggs. The muscles responsible for digging and both reproductive structures are under central neuronal control, incorporating neurons that express an array of neuropeptide and amine phenotype...
-
The effects of crustacean cardioactive peptide on locust Oviducts are calcium-dependent.
Peptides, 2002Co-Authors: Andrew Donini, Angela B. LangeAbstract:The role of calcium as a second messenger in the crustacean cardioactive peptide (CCAP)-induced contractions of the locust Oviducts was investigated. Incubation of the Oviducts in a calcium-free saline containing, a preferential calcium cation chelator, or an extracellular calcium channel blocker, abolished CCAP-induced contractions, indicating that the effects of CCAP on the Oviducts are calcium-dependent. In contrast, sodium free saline did not affect CCAP-induced contractions. Co-application of CCAP to the Oviducts with preferential L-type voltage-dependent calcium channel blockers reduced CCAP-induced contractions by 32-54%. Two preferential T-type voltage-dependent calcium channel blockers both inhibited CCAP-induced oviduct contractions although affecting different components of the contractions. Amiloride decreased the tonic component of CCAP-induced contractions by 40-55% and flunarizine dihydrochloride decreased the frequency of CCAP-induced phasic contractions by as much as 65%, without affecting tonus. Flunarizine dihydrochloride did not alter the proctolin-induced contractions of the Oviducts. Results suggest that the actions of CCAP are partially mediated by voltage-dependent calcium channels similar to vertebrate L-type and T-type channels. High-potassium saline does not abolish CCAP-induced contractions indicating the presence of receptor-operated calcium channels that mediate the actions of CCAP on the Oviducts. The involvement of calcium from intracellular stores in CCAP-induced contractions of the Oviducts is likely since, an intracellular calcium antagonist decreased CCAP-induced contractions by 30-35%.
-
crustacean cardioactive peptide is a modulator of oviduct contractions in locusta migratoria
Journal of Insect Physiology, 2001Co-Authors: Andrew Donini, Hansjurgen Agricola, Angela B. LangeAbstract:Crustacean cardioactive peptide (CCAP) stimulates the contractions of locust Oviducts. CCAP increased the basal tonus and increased the frequency and amplitude of phasic contractions, as well as the amplitude of neurally-evoked oviduct contractions in a dose-dependent manner. Oviducts from Vth instar larvae and adult locusts aged 10 days or less, were more sensitive to CCAP than Oviducts from adult locusts aged 12 days or more. This may be indicative of a differential expression of number or subtypes of CCAP receptors on the Oviducts at different ages, and may be related to reproductive functions or to functions of CCAP on the Oviducts during ecdysis. The Oviducts appear more sensitive to CCAP when compared with previously published reports of CCAP actions on the hindgut. CCAP actions on the amplitude of neurally-evoked contractions of the Oviducts are similar to those of proctolin, however, the Oviducts are more sensitive to CCAP. No CCAP-like immunoreactive structures were discovered in the nerves innervating the Oviducts, or on the Oviducts themselves, confirming the previously published suggestion (Dircksen et al., 1991) that CCAP acts as a neurohormone at the Oviducts. Cells showing CCAP-like immunoreactivity were discovered in the fat body associated with the Oviducts and represent a potential source of CCAP, along with CCAP released from the transverse nerve and perivisceral organs.
Wai Sum O - One of the best experts on this subject based on the ideXlab platform.
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
The Journal of Clinical Endocrinology and Metabolism, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: The objective of the study was to demonstrate the expression of ADM in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients, and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR, respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were cocultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell A...
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
Molecular Endocrinology, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: To demonstrate the expression of adrenomedullin (ADM) in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were co-cultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell ADM expression levels. CBF was also analyzed in oviductal tissue after spermatozoa-oviduct co-incubation. Results: ADM expression was the highest in the isthmic region and in a hormonal environment simulating the early luteal phase. CBF was increased by ADM in a dose-dependent manner which was blocked by ADM and calcitonin-gene-related peptide receptor antagonists. Direct contact with spermatozoa in co-culture resulted in higher ADM expression in OE-E6/E7 cell line and oviductal tissue, and higher CBF in oviductal epithelium. Conclusions: ADM expression in the human oviduct is hormone-dependent and is up-regulated by sperm contact. ADM stimulates ciliary motility of the human oviduct. Mol Endocrinol, July 2010, 24(7):1498–1499 mend.endojournals.org 1499
Toshihiko Fujimori - One of the best experts on this subject based on the ideXlab platform.
-
biophysics in oviduct planar cell polarity cilia epithelial fold and tube morphogenesis egg dynamics
Biophysics, 2019Co-Authors: Hiroshi Koyama, Toshihiko Fujimori, Dongbo ShiAbstract:Organs and tissues in multi-cellular organisms exhibit various morphologies. Tubular organs have multi-scale morphological features which are closely related to their functions. Here we discuss morphogenesis and the mechanical functions of the vertebrate oviduct in the female reproductive tract, also known as the fallopian tube. The oviduct functions to convey eggs from the ovary to the uterus. In the luminal side of the oviduct, the epithelium forms multiple folds (or ridges) well-aligned along the longitudinal direction of the tube. In the epithelial cells, cilia are formed orienting toward the downstream of the oviduct. The cilia and the folds are supposed to be involved in egg transportation. Planar cell polarity (PCP) is developed in the epithelium, and the disruption of the Celsr1 gene, a PCP related-gene, causes randomization of both cilia and fold orientations, discontinuity of the tube, inefficient egg transportation, and infertility. In this review article, we briefly introduce various biophysical and biomechanical issues in the oviduct, including physical mechanisms of formation of PCP and organized cilia orientation, epithelial cell shape regulation, fold pattern formation generated by mechanical buckling, tubulogenesis, and egg transportation regulated by fluid flow. We also mention about possible roles of the Oviducts in egg shape formation and embryogenesis, sinuous patterns of tubes, and fold and tube patterns observed in other tubular organs such as the gut, airways, etc.
-
analysis of ciliary beat frequency and ovum transport ability in the mouse oviduct
Genes to Cells, 2011Co-Authors: Kouji Komatsu, Tadashi Uemura, Toshihiko FujimoriAbstract:The oviduct is important in reproduction where fertilization occurs, and the fertilized eggs are conveyed to the uterus. Multi-ciliated cells of the oviductal epithelium and muscle contractions are believed to generate this unidirectional flow. Although there are many studies in human Oviducts, there are few reports on mouse oviductal ciliary movements where we can dissect underlying genetic programs. To study ciliary movements in the mouse oviduct, we exposed the ovary-side of the oviduct (infundibulum) longitudinally and recorded the ciliary beatings in a hanging drop preparation. We calculated the ciliary beat frequency (CBF) by automated image analysis and found that the average CBF was 10.9 ± 3.3 and 8.5 ± 2.5 Hz (±standard deviation) during the diestrus and estrus stages, respectively. Mapping of the CBF to multiple locations in the epithelium showed that the cilia beat regularly at a local level, but have a range of frequencies within the entire plane. We also observed ova with cumulus cells were transported to the uterus side by the opened oviduct at the diestrus and estrus stages. These results suggest that the ciliated cells of the infundibulum can generate unidirectional flows and are able to deliver ova by their ciliary activities despite their discordance in beating periodicity.
Hang Wu Raymond Li - One of the best experts on this subject based on the ideXlab platform.
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
The Journal of Clinical Endocrinology and Metabolism, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: The objective of the study was to demonstrate the expression of ADM in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients, and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR, respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were cocultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell A...
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
Molecular Endocrinology, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: To demonstrate the expression of adrenomedullin (ADM) in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were co-cultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell ADM expression levels. CBF was also analyzed in oviductal tissue after spermatozoa-oviduct co-incubation. Results: ADM expression was the highest in the isthmic region and in a hormonal environment simulating the early luteal phase. CBF was increased by ADM in a dose-dependent manner which was blocked by ADM and calcitonin-gene-related peptide receptor antagonists. Direct contact with spermatozoa in co-culture resulted in higher ADM expression in OE-E6/E7 cell line and oviductal tissue, and higher CBF in oviductal epithelium. Conclusions: ADM expression in the human oviduct is hormone-dependent and is up-regulated by sperm contact. ADM stimulates ciliary motility of the human oviduct. Mol Endocrinol, July 2010, 24(7):1498–1499 mend.endojournals.org 1499
William S B Yeung - One of the best experts on this subject based on the ideXlab platform.
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
The Journal of Clinical Endocrinology and Metabolism, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: The objective of the study was to demonstrate the expression of ADM in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients, and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR, respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were cocultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell A...
-
expression of adrenomedullin in human oviduct its regulation by the hormonal cycle and contact with spermatozoa and its effect on ciliary beat frequency of the oviductal epithelium
Molecular Endocrinology, 2010Co-Authors: Hang Wu Raymond Li, S Liao, Philip C N Chiu, James Chungman Ho, Ernest Hung Yu Ng, Pak Chung Ho, William S B Yeung, Fai Tang, Wai Sum OAbstract:Context: Adrenomedullin (ADM) has been found expressed in the mouse oviduct and might play a role in reproduction. Objective: To demonstrate the expression of adrenomedullin (ADM) in the human oviduct, investigate its regulation by steroidal hormones and spermatozoa contact, and study its effect on ciliary beat frequency (CBF) in the human oviduct. Design, Setting, Patients and Interventions: Oviducts from women undergoing hysterectomy for benign diseases in a university hospital were collected. The Oviducts were treated with estradiol and/or progesterone to simulate different phases of the ovarian cycle. ADM expression was studied at the peptide and mRNA levels by immunohistochemistry and RT-PCR respectively. CBF was measured after treatment with graded concentrations of ADM and its antagonists. Cells from OE-E6/E7, an immortalized oviductal cell line, as well as oviductal tissue were co-cultured with and without direct contact with capacitated human spermatozoa to compare oviductal cell ADM expression levels. CBF was also analyzed in oviductal tissue after spermatozoa-oviduct co-incubation. Results: ADM expression was the highest in the isthmic region and in a hormonal environment simulating the early luteal phase. CBF was increased by ADM in a dose-dependent manner which was blocked by ADM and calcitonin-gene-related peptide receptor antagonists. Direct contact with spermatozoa in co-culture resulted in higher ADM expression in OE-E6/E7 cell line and oviductal tissue, and higher CBF in oviductal epithelium. Conclusions: ADM expression in the human oviduct is hormone-dependent and is up-regulated by sperm contact. ADM stimulates ciliary motility of the human oviduct. Mol Endocrinol, July 2010, 24(7):1498–1499 mend.endojournals.org 1499
-
regulation of complement 3 protein expression in human and mouse Oviducts
Molecular Reproduction and Development, 2009Co-Authors: Yin Lau Lee, Ana Cheong, Wang Ngai Chow, Kaifai Lee, William S B YeungAbstract:The human oviduct derived embryotrophic factor-3 (ETF-3) contains complement protein-3 (C3) and its derivates. Although C3 is not embryotrophic, it is converted into the embryotrophic derivative, iC3b in the presence of embryos and oviductal cells. The regulation of C3 production in the oviduct is not known. The objectives of this study were to investigate the effects of presence of preimplantation embryos and hormones on C3 expression in the Oviducts in vitro and in vivo. The expression of C3 in the oviduct of pregnant mice was compared to that of pseudo-pregnant mice. The hormonal action on C3 expression was studied in the ovariectomized mouse Oviducts and human oviductal epithelial (OE) cells. The results showed that the level of C3 mRNA in the mouse oviduct was high on Day 1 and Day 2, but decreased to a minimum on Day 4 of pregnancy, whereas that of pseudo-pregnancy remained relatively stable within the same period. The protein levels of C3 and iC3b specific fragments, α-115 and α-40, respectively in the mouse oviductal luminal fluid were highest on Day 3 of pregnancy, when the embryos were expected to be most sensitive to the embryotrophic activity of ETF-3. Estrogen elevated C3 expression in the ovariectomized mouse oviduct and the OE cells. Progesterone suppressed estrogen-induced C3 expression in the mouse oviduct, but had no effect on OE cells. In conclusion, the presence of embryo and steroid hormones regulate the synthesis and secretion of oviductal C3. Mol. Reprod. Dev. 76: 301–308, 2009. © 2008 Wiley-Liss, Inc.
