Effect of bromocryptine on 20α-hydroxysteroiddehydrogenase regulation in the corpus luteum of the pregnant rat

1981 ◽  
Vol 98 (1) ◽  
pp. 133-136 ◽  
Author(s):  
K. Loewit ◽  
R. Kofler ◽  
M. Tabarelli ◽  
S. Schwarz
Keyword(s):  
Enzyme Activity ◽  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Placental Lactogen ◽  
Corpora Lutea ◽  
Sprague Dawley ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Sprague Dawley Rats ◽  
Effective Doses

Abstract. Pregnant Sprague Dawley rats were passively immunized with antiserum to bovine luteinizing hormone (anti-LH) on day 10 of pregnancy, and treated with 1 mg/day or 1.5 mg/day of the prolactin (Prl) inhibitor bromocryptine (BEC) between days 10 to 12 or 9 to 12, respectively. On day 12 a laparotomy was performed to assess the state of pregnancy and to remove the ovaries for histochemical detection of 20α-hydroxysteroiddehydrogenase (20α-OHSD) in the corpora lutea of pregnancy. In a second experiment pregnant rats were treated with 1.5mg BEC/day from days 17 to 22, checked for foetal state and ovariectomized on day 22 before giving birth. Treatment with BEC in effective doses did not interfere with anti-LH-induced termination of pregnancy and consequent reappearance of 20α-OHSD activity on day 12, or with spontanenous recurrence of enzyme activity at the end of gestation. It is concluded that Prl has no direct and immediate role in 20α-OHSD regulation, at least on day 12, although substitution by endogenous rat placental lactogen at the end of pregnancy cannot be excluded.

Evaluation of the Developmental Toxicity of α-Methyl-3,4-Methylene-Dioxyhydrocinnamic Aldehyde in Rats

2006 ◽  
Vol 25 (2) ◽  
pp. 127-132 ◽  
Author(s):  
Anne Marie Api ◽  
Elise M. Lewis ◽  
Alan M. Hoberman ◽  
Mildred S. Christian ◽  
Robert M. Diener
Keyword(s):  
Corn Oil ◽  
Developmental Toxicity ◽  
Clinical Signs ◽  
Feed Consumption ◽  
Corpora Lutea ◽  
Sprague Dawley ◽  
Pregnant Rats ◽  
Excessive Salivation ◽  
Sprague Dawley Rats ◽  
Body Weights

The developmental toxicity of α-methyl-3,4-methylene-dioxyhydrocinnamic aldehyde (MMDHCA), a widely used fragrance ingredient, was evaluated for developmental toxicity in Sprague-Dawley rats (25/group; cesarean-sectioning identified 21 to 25 pregnant rats/group). Oral dosages of 0 (corn oil), 62, 125, or 250 mg/kg/day were administered by gavage on days 7 through 17 of gestation (GDs 7 through 17). Rats were observed for viability, clinical signs, body weights, and feed consumption. Necropsy and cesarean sectioning occurred on GD 21. Uteri were examined for number and distribution of implantations, live and dead fetuses, and early and late resorptions. Numbers of corpora lutea were also recorded. Fetuses were weighed and examined for gender, gross external changes, and soft tissue or skeletal alterations. Analysis of dosage preparations verified calculated dosages ±10%. No deaths occurred. Excessive salivation occurred in all groups, but the incidence was increased at 250 mg/kg/day. The 250 mg/kg/day dosage also was associated with a significant increase in the incidences of a clear, red or yellow perioral and/or red perivaginal substance and significant reductions in mean feed consumption and body weight gains (11.6% and 7.4%, respectively) during the entire dosage period. No gross changes attributable to MMDHCA were observed at necropsy. Cesarean section or litter parameters, as well as fetal alterations, were not affected by MMDHCA at 250 mg/kg/day or either of the lower dosages tested. Based on these data, maternal and developmental no-observable-effect levels (NOAELs) of 125 and >250 mg/kg/day, respectively, were established for MMDHCA. It is concluded that MMDHCA is not a developmental toxicant in rats under the conditions of this study and dosing regimen.

EFFECT OF LUTEINIZING HORMONE ANTISERUM ON PROGESTERONE AND 20α-DIHYDROPROGESTERONE SECRETION IN THE PREGNANT RAT

1972 ◽  
Vol 52 (3) ◽  
pp. 413-418 ◽  
Author(s):  
N. R. MOUDGAL ◽  
H. R. BEHRMAN ◽  
R. O. GREEP
Keyword(s):  
Luteinizing Hormone ◽  
Cholesteryl Ester ◽  
Corpus Luteum ◽  
Free Cholesterol ◽  
Single Injection ◽  
Cholesterol Content ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Progesterone Secretion ◽  
Cholesteryl Ester Content

SUMMARY The effect of a single injection of luteinizing hormone (LH) antiserum on ovarian progesterone and 20α-dihydroprogesterone in day-8 and day-15 pregnant rats was studied. Within 24 h of an injection of LH antiserum, progesterone secretion was reduced by 80% in day-8 and by 25% in day-15 pregnant rats. The 20α-dihydroprogesterone levels after antiserum treatment were markedly increased in rats which were 8 days pregnant but reduced in rats which were 15 days pregnant. The free cholesterol content of the ovary did not change after antiserum injection but the cholesteryl ester content markedly increased. It is thus apparent that neutralization of endogenous LH resulted in a significant reduction in the progesterone secretion of the corpus luteum of the pregnant rat. The significance of these results is discussed.

Changes in thyroxine monodeiodination in rat liver, kidney and placenta during pregnancy

1984 ◽  
Vol 107 (4) ◽  
pp. 495-499 ◽  
Author(s):  
Katsumi Yoshida ◽  
Michiko Suzuki ◽  
Toshiro Sakurada ◽  
Hirofumi Kitaoka ◽  
Nobuko Kaise ◽  
...  
Keyword(s):  
Rat Liver ◽  
Time Course ◽  
Outer Ring ◽  
Sprague Dawley ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Sprague Dawley Rats ◽  
Tissue Homogenates ◽  
Liver And Kidney ◽  
Liver Homogenates

Abstract. Monodeiodination of thyrxoine (T4) was studied in the liver, kidney and placenta of pregnant rats. Age matched female non-pregnant and pregnant Sprague-Dawley rats on the 7th, 14th, 17th and 21st days of gestation were used. The 800 × g supernatants of tissue homogenates (protein 1 mg/tube) were incubated with 1 μg of stable T4 in the presence of 5 mm dithiothreitol (DTT) at 37°C for 60 min at pH 7.5. Net triiodothyronine (T3) generation from T4 in rat liver homogenates on the 7th day of gestation was significantly lower than that in the non-pregnant rat. Thereafter it increased, but values on the 14th, 17th and 21st days of gestation were not significantly different from those obtained in the non-pregnant rat. Net renal T3 generation from T4 on the 14th day was significantly lower than that in the non-pregnant rat. It was increased thereafter and the values at the 17th and 21st days of gestation were not significantly different from those in the non-pregnant rat. Net reverse T3 (rT3) generation from T4 in the placenta rose from the 14th to the 17th day and then dropped by the 21st day and the value at the 17th day was significantly higher than those at the 14th and 21st days of gestation. These results indcate that 1) both T4 outer-ring monodeiodination in the pregnant rat liver and kidney, and T4 inner-ring monodeiodination in the placenta show significant variation with the progress of gestation; 2) the time course of the T4 outer-ring monodeiodination in pregnant rat liver and kidney is completely different from T4 inner-ring monodeiodination in the placenta.

Enzymatic condensation of dopamine and acetaldehyde: a salsolinol synthase from rat brain

Biologia ◽  
2011 ◽  
Vol 66 (6) ◽  
Author(s):  
Xuechai Chen ◽  
Abida Arshad ◽  
Hong Qing ◽  
Rui Wang ◽  
Jianqing Lu ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Substantia Nigra ◽  
Human Subjects ◽  
Enzymatic Reaction ◽  
Brain Regions ◽  
Activity Detection ◽  
Reaction Products ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Salsolinol Synthase

AbstractSalsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline; Sal) is structurally similar to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, which is supposed to have a role in the development of Parkinson-like syndrome in both human and non-human subjects. In the human brain, the amount of (R)-enantiomer of Sal is much higher than (S)-enantiomer, suggesting that a putative enzyme may participate in the synthesis of (R)-salsolinol, called (R)-salsolinol synthase. In this study, the (R)-salsolinol synthase activity in the condensation of dopamine and acetaldehyde was investigated in the crude extracts from the brains of Sprague Dawley rats. Identification of the enzymatic reaction products and enzyme activity detection were achieved by HPLC-electrochemical detection. The discovery of this enzyme activity in rat’s brain indicates the natural existence of (R)-salsolinol synthase in the brains of humans and rats, and it is distributed in most brain regions of rat with higher activity in soluble proteins extracted from striatum and substantia nigra.

scholarly journals NIFEDIPINEON;

2019 ◽  
Vol 26 (02) ◽  
Author(s):  
Sidra Hamid ◽  
Qaiser Aziz ◽  
Aneela Jamil ◽  
Lubna Meraj ◽  
Shazia Muazam ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Luteinizing Hormone ◽  
Serum Testosterone ◽  
Serum Testosterone Level ◽  
Control Group ◽  
Channel Blockers ◽  
Sprague Dawley ◽  
Study Objective ◽  
Serum Luteinizing Hormone ◽  
Sprague Dawley Rats

Background: The most potent and effective drugs used for the management of blood pressure in hypertensive patients are Calcium channel blockers (CCBs). Nifedipine, a CCB, acts by blocking entry of calcium ions all the way through the voltage gated calcium channels (VGCCs) of L-type present in the smooth muscle cells of blood vesselsand reducing the blood pressure by decreasing the peripheral vascular resistance. Objectives: The study objective was to determine the effect of nifedipine on serum luteinizing hormone (LH) and serum testosterone in male Sprague Dawley rats. Study Design: Animal experimental study. Setting: All experiments were conducted at the Research laboratory of Shifa College of Medicine, Islamabad along with National Institute of Health (NIH), Islamabad. Period: October, 2012 to April, 2014. Methods: The study was done on adult male Sprague-Dawley rats (N= 60) aged 90-120 days old and their body weights varied between 200 + 50 grams. Rats were divided intotwo groups (n=30). Group A was administered0.5 ml distilled water/rat daily orally, group B was administered orally with nifedipine 50 mg/kg/rat dissolved in 1ml of DMSO. All the doses were given to rats for 8 weeks. After 8 weeks, serum luteinizing hormone and serum testosterone were measured in both groups. Results: In Nifedipine treated group, serum testosterone was significantly decreasedand serum LH was unaffected as compared to the control group. Conclusion: Nifedipine has adverse effects on male fertility as it decreases serum testosterone level.

CHANGES IN SERUM LEVELS OF FOLLICLE STIMULATING HORMONE AND LUTEINIZING HORMONE SHORTLY BEFORE AND AFTER PARTURITION IN RATS

1974 ◽  
Vol 75 (3) ◽  
pp. 491-496 ◽  
Author(s):  
Junichi Mori ◽  
Hiroshi Nagasawa ◽  
Reiko Yanai ◽  
Junji Masaki
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Serum Levels ◽  
Sprague Dawley ◽  
Appreciable Change ◽  
Serum Lh ◽  
Sprague Dawley Rats ◽  
Before And After ◽  
Average Serum ◽  
Stimulating Hormone

ABSTRACT The sequence of changes in the serum levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from 2 days before to 24 h after parturition of primiparous Sprague-Dawley rats was investigated by radioimmunoassay. No appreciable change in average serum FSH levels was observed during 2 days before and 1 h after parturition. After this the levels increased gradually to show a peak at 7 h after parturition and then declined gradually until 24 h after parturition. However, the level at 24 h after parturition was still twice as high as that at parturition (0 h). The average serum LH levels which were low between 2 days before and 1 h after parturition, showed a peak at 7 h and decreased toward 13 h after parturition. The same levels as at parturition were maintained between 13 and 24 h after parturition. The time of surge of either FSH or LH was closely related to the time after parturition. There were some differences between FSH and LH in the patterns of sequence of changes in the serum levels near parturition.

Ameliorating effects of cloperastine on dysfunction of the urinary bladder caused by cerebral infarction in conscious rats

2009 ◽  
Vol 87 (11) ◽  
pp. 893-899 ◽  
Author(s):  
Gen Yamamoto ◽  
Fumio Soeda ◽  
Tetsuya Shirasaki ◽  
Kazuo Takahama
Keyword(s):  
Urinary Bladder ◽  
Cerebral Infarction ◽  
Flow Rate ◽  
Bladder Capacity ◽  
Left Middle Cerebral Artery ◽  
Sprague Dawley ◽  
Urinary Bladder Dysfunction ◽  
Sprague Dawley Rats ◽  
Urethral Resistance ◽  
Effective Doses

We investigated the effects of the centrally acting antitussives dextromethorphan and cloperastine on urinary bladder dysfunction 24 h after cerebral infarction in rats using the cystometry technique. First, cystometrography was performed in conscious male Sprague–Dawley rats. Cerebral infarction was then induced by occlusion of the left middle cerebral artery. Twenty-four hours after cerebral infarction, the effect of each drug on micturition disorder was estimated for 5 parameters: bladder capacity, maximum voiding pressure, micturition latency, flow rate, and urethral resistance. Cerebral infarction markedly reduced bladder capacity, micturition latency, and flow rate and increased urethral resistance. After cerebral infarction, intravenous dosing of saline had no effect on these parameters. Dextromethorphan (20 mg/kg) and cloperastine (2.5 and 5.0 mg/kg) at antitussive effective doses significantly increased bladder capacity and micturition latency. Unlike dextromethorphan, cloperastine ameliorated decreases in flow rate and increases in urethral resistance caused by cerebral infarction. These results suggest that cloperastine may have therapeutic value for the treatment of disorders of the micturition reflex associated with cerebral infarction, and that the drug may become a base compound from which to develop more active drugs for such disorders.

CYCLISCHE SCHWANKUNGEN DER AKTIVITÄTEN VON HYDROXYSTEROID-DEHYDROGENASEN IM CORPUS LUTEUM DES RINDES

1972 ◽  
Vol 69 (2) ◽  
pp. 369-384
Author(s):  
H. Brandau ◽  
L. Brandau ◽  
G. Mutzke
Keyword(s):  
Enzyme Activity ◽  
Corpus Luteum ◽  
Enzyme Activities ◽  
Optical Method ◽  
Activity Patterns ◽  
Hydroxysteroid Dehydrogenase ◽  
Corpora Lutea ◽  
Bovine Corpus Luteum ◽  
Glucose 6 Phosphate Dehydrogenase

ABSTRACT In the bovine corpora lutea periodical activities of the Δ53β-, 3β-, 17β-and 20β-hydroxysteroid dehydrogenase (OHSDH) as well as activities of glyceraldehyde-3-phosphate- and glucose-6-phosphate dehydrogenase were measured quantitatively and the alterations throughout the different stages of the cycle were studied. After homogenization of the tissue and fractionate centrifugation the enzyme activities were determined by a standardized optical method. The activities of the Δ53β-, and 3β- and 17β-OHSDH increase slowly during the first 7 days of the cycle, the maximum is reached abruptly on the 12th to 13th day of the cycle. After a striking reduction the activities decline continually to the 19th to 21st day reaching the values detected at the beginning of the cycle. The 20β-OHSDH increases slowly to the maximum on the 15th day of the cycle. Activities of the 3α-OHSDH were obtained only inconsistently. The behaviour of the activities of G6PDH was nearly identical with that of the 3β-OHSDH, while the GAPDH shows only little fluctuations of its activities. The obtained enzyme activity patterns of the maturating and high functional corpus luteum correspond to the well-known data of the biosynthetic function of the bovine corpus luteum. The changes of the amounts of progesterone and 20β-progesterol agree with the course of the activities of the 3β- resp. 20β-OHSDH.

PLASMA AND PITUITARY LUTEINIZING HORMONE CONCENTRATIONS AND PERIPHERAL PLASMA OESTRADIOL CONCENTRATION DURING EARLY PREGNANCY AND AFTER THE ADMINISTRATION OF PROGESTATIONAL STEROIDS IN THE RAT

1972 ◽  
Vol 53 (1) ◽  
pp. 31-35 ◽  
Author(s):  
K. BROWN-GRANT ◽  
C. S. CORKER ◽  
F. NAFTOLIN
Keyword(s):  
Luteinizing Hormone ◽  
Marked Decrease ◽  
Single Injection ◽  
Normal Pregnancy ◽  
Oestrous Cycle ◽  
Pregnant Rats ◽  
Pregnant Rat ◽  
Peripheral Plasma ◽  
Blastocyst Implantation ◽  
Plasma Oestradiol

SUMMARY Plasma luteinizing hormone (LH) concentrations were already lower on Day 2 of pregnancy than at the same time after the preceding ovulation in the non-pregnant rat, and fell progressively up to Day 16 of pregnancy. No evidence was obtained of any increase at the time when the ovulatory surge of LH would have occurred if the animal had not become pregnant. Pituitary LH concentration was lower in mated rats on the morning of Day 0 of pregnancy than in unmated controls on the morning of the day of oestrus. Subsequently it increased slowly to reach a level higher than at any stage of the oestrous cycle by Day 8 of pregnancy and remained high until at least Day 16 of pregnancy. Peripheral plasma oestradiol concentration increased late on Day 2 of pregnancy and was still raised on Day 4 but was never more than about one fourth of the peak concentration seen on the morning of prooestrus during the oestrous cycle. There were similar changes in plasma LH and oestradiol concentrations in the 48 h after a single injection of 2·5mg progesterone on the morning of the day of dioestrus, a procedure that delays ovulation by 1 or 2 days. Administration of a synthetic progestational compound (medroxyprogesterone acetate) to pregnant rats delayed blastocyst implantation and the delay was associated with a marked decrease in peripheral plasma LH to levels below those of normal pregnancy.

scholarly journals Prolactin independent rescue of mouse corpus luteum life span: identification of prolactin and luteinizing hormone target genes

2009 ◽  
Vol 297 (3) ◽  
pp. E676-E684 ◽  
Author(s):  
Anne Bachelot ◽  
Julie Beaufaron ◽  
Nathalie Servel ◽  
Cécile Kedzia ◽  
Philippe Monget ◽  
...  
Keyword(s):  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Ovarian Function ◽  
De Novo ◽  
Embryo Implantation ◽  
Receptor Expression ◽  
Corpora Lutea ◽  
Mrna Expression Profiling

The corpus luteum (CL) plays a central role in the maintenance of pregnancy in rodents, mainly by secreting progesterone. Female mice lacking prolactin (PRL) receptor (R) are sterile due to a failure of embryo implantation, which is a consequence of decreased luteinizing hormone (LH) receptor expression in the CL and inadequate levels of progesterone. We attempted to treat PRLR−/− females with human chorionic gonadotropin (hCG) and showed a de novo expression of LHR mRNA in the corpora lutea. Binding analysis confirmed that the LHR in hCG-treated PRLR−/− animals was functional. This was accompanied with increased expression of steroidogenic enzymes involved in progesterone synthesis. Despite these effects, no embryo implantation was observed because of high expression of 20α-hydroxysteroid dehydrogenase. To better appreciate the molecular mechanisms underlying maintenance of the CL, a series of mRNA expression-profiling experiments was performed on isolated corpora lutea of PRLR−/− and hCG-treated PRLR−/− mice. This approach revealed several novel candidate genes with potentially pivotal roles in ovarian function, among them, p27, VE-cadherin, Pten, and sFRP-4, a member of the Wnt/frizzled family. This study showed the differential role of PRL and LH in CL function and identified new targets of these hormones in luteal cells.

Sign in / Sign up

Export Citation Format

Share Document