scholarly journals Neonatal Exposure to 17α-Ethinyl Estradiol Affects Kisspeptin Expression and LH-Surge Level in Female Rats

2014 ◽  
Vol 76 (8) ◽  
pp. 1105-1110 ◽  
Author(s):  
Kento USUDA ◽  
Kentaro NAGAOKA ◽  
Kaori NOZAWA ◽  
Haolin ZHANG ◽  
Kazuyoshi TAYA ◽  
...  
Keyword(s):  
Ethinyl Estradiol ◽  
Female Rats ◽  
Neonatal Exposure ◽  
Lh Surge

scholarly journals Persistent vs transient alteration of folliculogenesis and estrous cycle after neonatal vs adult exposure to Bisphenol A

Endocrinology ◽  
2019 ◽  
Author(s):  
David López-Rodríguez ◽  
Delphine Franssen ◽  
Elena Sevrin ◽  
Arlette Gérard ◽  
Cédric Balsat ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Estrous Cycle ◽  
Corn Oil ◽  
Female Rats ◽  
Neonatal Exposure ◽  
High Dose ◽  
Corpora Lutea ◽  
Lh Surge ◽  
Primordial Follicles ◽  
Adult Exposure

Abstract Exposure to Bisphenol A (BPA), a ubiquitous endocrine disrupting chemical (EDC) is known to produce variable effects on female puberty and ovulation. This variability of effects is possibly due to differences in dose and period of exposure. Little is known about the effects of adult exposure to environmentally relevant doses of this EDC and the differences in effect after neonatal exposure. This study aims at comparing the effects of neonatal versus adult exposure to a very low or a high dose of BPA for two weeks on ovulation and folliculogenesis and exploring the hypothalamic mechanisms involved in such disruption by BPA. One day-old and 90 day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25 ng/kg/d or 5 mg/kg/d) for 15 days. Neonatal exposure to both BPA doses significantly disrupted the estrous cycle and induced a decrease in primordial follicles. Effects on estrous cyclicity and folliculogenesis persisted into adulthood, consistent with a disruption of organizational mechanisms. During adult exposure, both doses caused a reversible decrease in antral follicles and corpora lutea. A reversible disruption of the estrous cycle associated with a delay and a decrease in the amplitude of the LH surge was also observed. Alterations of the hypothalamic expression of the clock gene Per1 and the novel reproductive peptide Phoenixin indicated a disruption of the hypothalamic control of the preovulatory LH surge by BPA.

Is the estrogen-induced LH-surge in female rats triggered by noradrenalin or adrenalin?

1986 ◽  
Vol 113 (1_Suppl) ◽  
pp. S92-S93
Author(s):  
C. HIEMKE ◽  
A. SCHMIDT ◽  
R. GHRAF
Keyword(s):  
Female Rats ◽  
Lh Surge

Neonatal exposure to estradiol-17β modulates tumour necrosis factor alpha and cyclooxygenase-2 expression in brain and also in ovaries of adult female rats

2016 ◽  
Vol 25 (2) ◽  
Author(s):  
Radhika Nagamangalam Shridharan ◽  
Harshini Krishnagiri ◽  
Vijayakumar Govindaraj ◽  
SitiKantha Sarangi ◽  
Addicam Jagannadha Rao
Keyword(s):  
Recent Observation ◽  
Endocrine Disrupting Compounds ◽  
Perinatal Period ◽  
Female Rats ◽  
Neonatal Exposure ◽  
Sexually Dimorphic ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
And Behavior ◽  
Estradiol 17Β

AbstractThe sexually dimorphic organization in perinatal rat brain is influenced by steroid hormones. Exposure to high levels of estrogen or endocrine-disrupting compounds during perinatal period may perturb this process, resulting in compromised reproductive physiology and behavior as observed in adult In our recent observation neonatal exposure of the female rats to estradiol-17β resulted in down-regulation of

scholarly journals The Increase in Signaling by Kisspeptin Neurons in the Preoptic Area and Associated Changes in Clock Gene Expression That Trigger the LH Surge in Female Rats Are Dependent on the Facilitatory Action of a Noradrenaline Input

Endocrinology ◽  
2016 ◽  
Vol 157 (1) ◽  
pp. 323-335 ◽  
Author(s):  
Bruna Kalil ◽  
Aline B. Ribeiro ◽  
Cristiane M. Leite ◽  
Ernane T. Uchôa ◽  
Ruither O. Carolino ◽  
...  
Keyword(s):  
Gene Expression ◽  
Median Eminence ◽  
Preoptic Area ◽  
Clock Genes ◽  
Third Ventricle ◽  
Female Rats ◽  
Ovariectomized Rats ◽  
Lh Surge ◽  
Clock Gene Expression

Abstract In rodents, kisspeptin neurons in the rostral periventricular area of the third ventricle (RP3V) of the preoptic area are considered to provide a major stimulatory input to the GnRH neuronal network that is responsible for triggering the preovulatory LH surge. Noradrenaline (NA) is one of the main modulators of GnRH release, and NA fibers are found in close apposition to kisspeptin neurons in the RP3V. Our objective was to interrogate the role of NA signaling in the kisspeptin control of GnRH secretion during the estradiol induced LH surge in ovariectomized rats, using prazosin, an α1-adrenergic receptor antagonist. In control rats, the estradiol-induced LH surge at 17 hours was associated with a significant increase in GnRH and kisspeptin content in the median eminence with the increase in kisspeptin preceding that of GnRH and LH. Prazosin, administered 5 and 3 hours prior to the predicted time of the LH surge truncated the LH surge and abolished the rise in GnRH and kisspeptin in the median eminence. In the preoptic area, prazosin blocked the increases in Kiss1 gene expression and kisspeptin content in association with a disruption in the expression of the clock genes, Per1 and Bmal1. Together these findings demonstrate for the first time that NA modulates kisspeptin synthesis in the RP3V through the activation of α1-adrenergic receptors prior to the initiation of the LH surge and indicate a potential role of α1-adrenergic signaling in the circadian-controlled pathway timing of the preovulatory LH surge.

scholarly journals Effect of androgen on Kiss1 expression and luteinizing hormone release in female rats

2017 ◽  
Vol 233 (3) ◽  
pp. 281-292 ◽  
Author(s):  
Kinuyo Iwata ◽  
Yuyu Kunimura ◽  
Keisuke Matsumoto ◽  
Hitoshi Ozawa
Keyword(s):  
Luteinizing Hormone ◽  
Arcuate Nucleus ◽  
Female Rats ◽  
Hormone Release ◽  
Lh Surge ◽  
Continuous Release ◽  
Ovulatory Dysfunction ◽  
Lh Release ◽  
Gonadotrophin Releasing Hormone ◽  
Lh Secretion

Hyperandrogenic women have various grades of ovulatory dysfunction, which lead to infertility. The purpose of this study was to determine whether chronic exposure to androgen affects the expression of kisspeptin (ovulation and follicle development regulator) or release of luteinizing hormone (LH) in female rats. Weaned females were subcutaneously implanted with 90-day continuous-release pellets of 5α-dihydrotestosterone (DHT) and studied after 10 weeks of age. Number of Kiss1-expressing cells in both the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) was significantly decreased in ovary-intact DHT rats. Further, an estradiol-induced LH surge was not detected in DHT rats, even though significant differences were not observed between DHT and non-DHT rats with regard to number of AVPV Kiss1-expressing cells or gonadotrophin-releasing hormone (GnRH)-immunoreactive (ir) cells in the presence of high estradiol. Kiss1-expressing and neurokinin B-ir cells were significantly decreased in the ARC of ovariectomized (OVX) DHT rats compared with OVX non-DHT rats; pulsatile LH secretion was also suppressed in these animals. Central injection of kisspeptin-10 or intravenous injection of a GnRH agonist did not affect the LH release in DHT rats. Notably, ARC Kiss1-expressing cells expressed androgen receptors (ARs) in female rats, whereas only a few Kiss1-expressing cells expressed ARs in the AVPV. Collectively, our results suggest excessive androgen suppresses LH surge and pulsatile LH secretion by inhibiting kisspeptin expression in the ARC and disruption at the pituitary level, whereas AVPV kisspeptin neurons appear to be directly unaffected by androgen. Hence, hyperandrogenemia may adversely affect ARC kisspeptin neurons, resulting in anovulation and menstrual irregularities.

scholarly journals Pup removal suppresses estrogen-induced surges of LH secretion and activation of GnRH neurons in lactating rats

2006 ◽  
Vol 191 (1) ◽  
pp. 339-348 ◽  
Author(s):  
Atsushi Fukushima ◽  
Ping Yin ◽  
Maho Ishida ◽  
Nobuhiro Sugiyama ◽  
Jun Arita
Keyword(s):  
Third Ventricle ◽  
Acute Effect ◽  
Suppressive Effect ◽  
Female Rats ◽  
Ovariectomized Rats ◽  
Indwelling Catheter ◽  
Lh Surge ◽  
Gnrh Neurons ◽  
Double Immunohistochemical Staining ◽  
Lh Secretion

During lactation, the suckling stimulus exerts profound influences on neuroendocrine regulation in nursing rats. We examined the acute effect of pup removal on the estrogen-induced surge of LH secretion in ovariectomized lactating rats. Lactating and nonlactating cyclic female rats were given an estradiol-containing capsule after ovariectomy, and blood samples were collected through an indwelling catheter for serum LH determinations. In lactating, freely suckled ovariectomized rats, estrogen treatment induced an afternoon LH surge with a magnitude and timing comparable to those seen in nonlactating rats. Removal of pups from the lactating rats at 0900, 1100, or 1300 h, but not at 1500 h, suppressed the estrogen-induced surge that normally occurs in the afternoon of the same day. The suppressive effect of pup removal at 0900 h was completely abolished when the pups were returned by 1400 h. In contrast, pup removal was ineffective in abolishing the stimulatory effect of progesterone on LH surges. Double immunohistochemical staining for gonadotropin-releasing hormone (GnRH) and c-Fos, a marker for neuronal activation, revealed a decrease, concomitantly with the suppression of LH surges, in the number of c-Fos-immunoreactive GnRH neurons in the preoptic regions of nonsuckled rats. An LH surge was restored in nonsuckled rats when 0.1 μg oxytocin was injected into the third ventricle three times at 1-h intervals during pup removal. These results suggest that the GnRH surge generator of lactating rats requires the suckling stimulus that is not involved in nonlactating cyclic female rats.

Neonatal exposure to bisphenol A alters the hypothalamic-pituitary-thyroid axis in female rats

2018 ◽  
Vol 285 ◽  
pp. 81-86 ◽  
Author(s):  
Marina O. Fernandez ◽  
Nadia S. Bourguignon ◽  
Paula Arocena ◽  
Matías Rosa ◽  
Carlos Libertun ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Female Rats ◽  
Neonatal Exposure ◽  
Pituitary Thyroid Axis ◽  
Thyroid Axis

Reproductive effects in male and female rats from neonatal exposure to p-octylphenol

2001 ◽  
Vol 15 (6) ◽  
pp. 683-692 ◽  
Author(s):  
T Nagao ◽  
S Yoshimura ◽  
Y Saito ◽  
M Nakagomi ◽  
K Usumi ◽  
...  
Keyword(s):  
Female Rats ◽  
Neonatal Exposure ◽  
Male And Female ◽  
Reproductive Effects ◽  
Male And Female Rats

Prolonged Neonatal Exposure to Estrogen Inhibits Pulsatile LH Release and Estrous Cyclicity in Female Rats Probably Via Disruption of the Arcuate Metastin/Kisspeptin Neurons.

2008 ◽  
Vol 78 (Suppl_1) ◽  
pp. 146-146
Author(s):  
Yoko Inamoto ◽  
Tamami Homma ◽  
Yoshihisa Uenoyama ◽  
Maki Maeda ◽  
Shunji Yamada ◽  
...  
Keyword(s):  
Female Rats ◽  
Neonatal Exposure ◽  
Estrous Cyclicity ◽  
Lh Release

scholarly journals Minireview: Timely Ovulation: Circadian Regulation of the Female Hypothalamo-Pituitary-Gonadal Axis

Endocrinology ◽  
2006 ◽  
Vol 147 (3) ◽  
pp. 1148-1153 ◽  
Author(s):  
Horacio O. de la Iglesia ◽  
William J. Schwartz
Keyword(s):  
Suprachiasmatic Nucleus ◽  
Clock Genes ◽  
Female Rats ◽  
Circadian Regulation ◽  
Pituitary Cells ◽  
Neural Oscillators ◽  
Lh Surge ◽  
Pharmacological Data ◽  
Circadian Clock Genes ◽  
Estradiol Levels

The preovulatory surge in the secretion of LH is timed by a neuroendocrine integrative mechanism that involves ovarian estradiol levels and the endogenous circadian system. Studies in female rats and hamsters have established that the clock in the hypothalamic suprachiasmatic nucleus has a preeminent role in setting the LH surge, and anatomical, physiological, and pharmacological data are revealing the responsible connections between suprachiasmatic nucleus neurons and GnRH and estradiol-receptive areas. Recent investigations show that GnRH and pituitary cells express circadian clock genes that might play a role in the release and reception of the GnRH signal. Analysis of the circadian regulation of the LH surge may provide a model for understanding how multiple neural oscillators function within other neuroendocrine axes.

Sign in / Sign up

Export Citation Format

Share Document