Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00691 (EE2)
 7,802 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this experiment was to determine whether surgical stress on the morning of proestrus would elicit an early release of gonadotropin from the pituitary. Animals exhibiting 5-day estrous cycles underwent bilateral sham-ovariectomy under ether anesthesia at 0800 h of proestrus. These animals had high levels of progesterone and estradiol following the surgery. These steroids were thought to be adrenal in origin, since animals adrenalectomized at 0800 h of proestrus had low progesterone levels and estradiol comparable to unoperated controls. Subsequently, the sham-operated animals showed high FSH but not LH values at 1300 h, prior to the normal critical period for gonadotropin release. By 1400, the LH surge had begun, and progesterone was again being released. Adrenalectomized and unoperated controls showed no increase in any steroid or gonadotropin measured before 1400 h. These findings suggest that stress-induced release of adrenal estradiol and progesterone, rather than some other consequence of the surgical procedure, during the morning of proestrus, can advance the onset of release of FSH, prior to LH. Ovariectomy at 0800 h proestrus led to a rapid and dramatic increase in FSH but not LH secretion by 4 h after surgery. By 6 h after ovariectomy FSH had increased to six times control values and LH had increased to twice control values. Estradiol remained at control values for 6 h following surgery but 20alpha-hydroxypreg-4-en-3-one (20alpha-OHP) dropped quickly to baseline values. It is possible that a reduction in circulating 20 alpha-OHP may be responsible for the increases in FSH prior to LH in this group, but the absence of other negative feedback factors from the ovary or adrenal may also be involved.
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PMID:Alterations in steroid and gonadotropin release resulting from surgical stress during the morning of proestrus in 5-day cyclic rats. 123 90

A group of 217 women of 350 IUD users with missing IUD threads were enrolled in the investigation. The final sample of the comparative trial involved 197 patients with retrievable threads which could not be brought below the external os with Spencer Wells forceps. 143 (73%) used Gravigard; 19 (10%) the Mini-Gravigard; 21 (10%) other copper-bearing devices (Multiload, Mini-Multiload, Novagard, Ortho-Gyne-T); and 12 (6%) the Lippes Loop, while in the remaining 2 (1%) the type of device was not recorded. The endocervical canal of all women was explored with a Spencer Wells forceps, and 2 randomly chosen plastic IUD thread retrievers were used to capture the missing threads. The threads were retrieved with Spencer Wells forceps alone in about 40% of patients, and with the disposable plastic retrievers in another 40%. About 5% had not retrievable threads, and only 2-5% of the patients required general anesthesia for IUD removal. The 1st plastic retriever succeeded in removing the device in 50% of patients. The Retrievette (59%) and the Emmett (53%) performed better than the Mi-Mark Helix (37%) yielding a statistically significant difference (P=0.03). The 95% confidence interval for the difference of the Mi-Mark Helix from the other 2 retrievers was 4% to 33%. The success rates of a 2nd plastic retriever randomly chosen from 2 retrievers not used in the 1st attempt were 63%, 56%, and 36%, analogous to rates with the 1st plastic retrievers. 33 of the 47 women in whom the plastic retrievers failed, had the threads/IUDS retrieved with a metal hook, preferably with the Birnberg hook. The initial exploration of the endocervical canal with Spencer Wells forceps proved valuable, and if it fails either the Retrievette or the Emmett thread retrievers are effective in general practice or in family planning clinics.
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PMID:Randomised comparative study in 217 women of three disposable plastic IUCD thread retrievers. 145 Jan 43

This article reviews current understanding of the physiological control of maternal behaviour in parturient ewes. Estradiol is an important endocrine factor which stimulates maternal responsiveness, both in nonpregnant and in parturient ewes. However, its action depends on previous maternal experience, and other factors are also necessary for the rapid manifestation of maternal behaviour. Olfactory cues play a major role in the normal development of the mother-young relationship. Genital stimulation (GS) is a key factor influencing various aspects of maternal responsiveness in sheep. GS acts in synergy with peripheral hormones to induce the rapid onset of licking and immediate acceptance of a neonate at the udder in nonpregnant ewes. It also influences the attraction of amniotic fluid at parturition and reduces aggressive behaviour towards lambs. Deprivation of GS by peridural anesthesia disturbs maternal behaviour in parturient ewes, especially in primiparae. And, additional GS in postparturient ewes allows the formation of a new bond with an alien neonate in mothers which had already established a selective relationship with their own lambs. Some of these positive effects of GS are mediated through modifications of olfactory function (attraction of amniotic fluid, establishment of a selective bond), whereas this may not be the case for other effects (stimulation of licking, reduction of aggressive behaviour). Studies of the neural mechanisms involved will be necessary to specify the modes of action of GS. The first results suggest GS may act in at least two ways at the level of the brain. Stimulation of maternal behaviour could depend on the liberation of oxytocin within the brain, since intracerebroventricular injections of this hormone facilitate maternal responses. Also, GS can influence olfactory function through the activation of afferent noradrenergic pathways in the olfactory bulbs. Further studies need to be developed to specify the relationships between the various structures involved as well as the level at which estradiol exerts its facilitatory action.
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PMID:Genital, olfactory, and endocrine interactions in the development of maternal behaviour in the parturient ewe. 328 20

In cycling rats, pituitary concentrations of luteinizing hormone (LH) beta-subunit mRNA increase two- to threefold before the afternoon proestrus LH surge without a corresponding increase in alpha-subunit mRNA. Estradiol (E2) treatment is known to allow expression of daily LH surges in ovariectomized (OVX) rats, and the timing, magnitude, and duration of LH secretion is similar to the LH surge on proestrus. The present study was conducted to examine whether the regulation of LH subunit mRNAs during the LH surge in OVX-E2-treated rats is similar to that present on proestrus. Female Holtzman rats were OVX and Silastic implants containing E2 were inserted subcutaneously under ether anesthesia. Some animals received bromocriptine (0.6 mg sc, twice/day beginning 1 h before surgery). On the 2nd day after surgery, groups of animals (n = 4-10/group) were decapitated at intervals between 1000 and 2100. LH and prolactin (PRL) levels were measured in trunk blood. LH subunit mRNA concentrations in the pituitaries were measured by dot-blot hybridization assay. In OVX-E2 rats the LH surge occurred at 1830 and was accompanied by a selective twofold increase in alpha-subunit mRNA (from 266 +/- 18 to 459 +/- 61 pg cDNA bound/100 micrograms pituitary DNA) and maximum values were present at 1730. LH beta-subunit mRNA (m = 29 +/- 1 pg cDNA bound/100 micrograms pituitary DNA) was unchanged throughout the day. Bromocriptine treatment resulted in the suppression of serum PRL (m = 23 +/- 2 ng/ml) and the LH surge was delayed by 1-1.5 h and somewhat blunted.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:LH subunit mRNA concentrations during LH surge in ovariectomized estradiol-replaced rats. 333 27

Cycling adult female hamsters can be induced to mate and ovulate 24 h early by the injection of 20 IU human chorionic gonadotropin (hCG) at 1500 h on Day 3 (day before proestrus), but pregnancy is not established. Although there is evidence of decreased sperm transport in precociously ovulated females, this does not appear to be the primary cause of infertility. Reduced size and vascularity of corpora lutea (CL) in treated females suggests incomplete or failed CL activation. Control and hCG-treated females were killed by exsanguination under ether anesthesia at intervals for the first 5 days after mating. Serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, estradiol, and progesterone were measured by radioimmunoassay. Luteinizing hormone in treated animals was very high at 2200 h on Day 1 after mating (31 h after the hCG injection), due to endogenous release, and dropped below control levels thereafter. Follicle-stimulating hormone, by contrast, was significantly lower than controls at 2200 h on Day 1 and remained low until 2200 h on Day 3 after mating. Prolactin in treated animals was not different from that in controls, except for 1000 h on Day 4, when it showed a significant dip. Estradiol in treated animals was significantly higher than in controls at 2200 h on Day 1 (when LH was also high and FSH was low), and remained high at 1000 h and 2200 h on Day 2, dropping thereafter to control levels. Progesterone was initially at control levels but had dropped significantly by 1000 h on Day 2 and remained low for the next 24 h. These results suggest that pregnancy failure is due to inadequate activation of corpora lutea. This may be due to: 1) immaturity of follicles at the time of ovulation; 2) inappropriate timing of preovulatory events; 3) the luteolytic effects of high levels of LH or estradiol or both; 4) the low level of FSH in the early stages of corpus luteum development; or 5) a combination of the above. Abnormalities of prolactin secretion were not investigated in detail but cannot be ruled out at this time.
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PMID:Multiple causes of pregnancy failure in hamsters precociously ovulated by human chorionic gonadotropin. 393 83

Ortho-iodo sodium benzoate (OISB) decreases the affinity of blood for oxygen, thus enhancing potential tissue oxygen delivery. To test the hypothesis that a change in oxygen affinity would ameliorate regional myocardial ischemic injury resulting from occlusion of the left anterior descending (LAD) coronary artery, experiments were carried out in 55 anesthetized dogs which received an intravenous infusion of OISB. In Protocol I studies (n = 9), preocclusion intravenous infusion of OISB (500 mg/kg) reduced epicardial S-T segment elevation 15 minutes after coronary occlusion, while a similar volume of normal saline solution did not affect this index of ischemic damage. In Protocol II experiments, 34 dogs were randomized to either an OISB or saline group, after which the LAD was ligated, the chest closed, and the animal allowed to recover from anesthesia. Myocardial infarction (MI) size was assessed after the animal died or was killed 8 to 24 hours later, and was found to be 29% smaller in dogs receiving OISB. In 6 dogs, blood P50 (the partial oxygen pressure at which hemoglobin is 50% saturated with oxygen) was increased by OISB infusion, confirming that its administration effected a rightward shift in the oxyhemoglobin dissociation curve. Protocol III studies assessed the effects of OISB on cardiac hemodynamic function and acute myocardial ischemic damage when infusion was begun 15 minutes after LAD occlusion: average epicardial S-T segment elevation was not altered by saline solution, but decreased when OISB was infused during the last 15 minutes of myocardial ischemia. Reductions in heart rate, left ventricular dP/dt, and cardiac output were observed in 7 dogs during OISB infusion, but there were no changes in these measurements during coronary occlusion in 5 dogs receiving a constant infusion of saline solution. There were no changes in regional myocardial blood flow (microsphere technique) to either ischemic or nonischemic zones in either the saline control or OISB treatment groups. Thus, both acute myocardial ischemic injury (assessed by epicardial electrocardiographic mapping) and ultimate MI size are reduced when OISB is infused before experimental coronary artery occlusion. OISB also reduces myocardial ischemic injury when its administration is begun 15 minutes after coronary occlusion, while effecting decreases in heart rate, left ventricular contractility, and cardiac output.
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PMID:Effects of ortho-iodo sodium benzoate on acute myocardial ischemia, hemodynamic function, and infarct size after coronary artery occlusion in dogs. 684 70

The synthetic estrogen component of many oral contraceptives, 17 alpha-ethynylestradiol-17 beta (EE2) and the naturally occurring estrogen, estradiol-17 beta (E2) were studied in four pregnant rhesus monkeys (71% term: 108-121 days gestational age). Under ketamine anesthesia, catheters were implanted in the maternal femoral artery and fetal interplacental artery. After simultaneous i.v. administration of [3H]EE2-[14C]E2 to the maternal animal, serial blood samples were drawn from both mother and fetus. The estrogens and metabolites were identified and quantified by the comigration of radioactivity with reference standards in several high-performance liquid chromatography systems and subsequent selective enzyme hydrolysis of the conjugates. Only estrone (E1), E1 sulfate, EE2 and EE2-3 sulfate were observed in the fetal circulation, whereas the major radiolabeled compounds in the maternal circulation consisted of the above plus E2, E1 glucuronide and EE2-3 glucuronide. In order to determine whether the placenta could convert E2 to its metabolite E1, the placentas of three term rhesus monkeys were perfused in situ via the umbilical artery with 120 ml (15 ml/min) of Hanks' balanced salt solution (pH 7.4) containing [3H]E2. High-performance liquid chromatographic analysis of umbilical vein samples revealed that 96% of the E2 was metabolized to E1. These studies indicate that the placenta can metabolize the potent naturally occurring estrogen E2 to the less potent E1. In contrast, the synthetic estrogen EE2 does not undergo this placental metabolic conversion and thus enters the fetal circulation as the parent compound.
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PMID:Placental transfer and metabolism of 17 alpha-ethynylestradiol-17 beta and estradiol-17 beta in the rhesus monkey. 713 2

In baboons as in humans, the placenta is a source of various peptides, including pregnancy-associated plasma protein-A (PAPP-A). However, our present understanding of the regulation of PAPP-A production is incomplete. We have demonstrated that after fetectomy, the baboon placenta retains steroidogenic capacity and is maintained in utero until delivered spontaneously close to term. We have suggested, therefore, that fetectomy provides a valuable in vivo approach to elucidating the role(s) of the fetus, and of the hormones (e.g., estrogen and progesterone) dependent upon the presence of the fetus, in the regulation of placental steroidogenesis during primate pregnancy. Therefore in the present study we utilized the fetectomy model to evaluate the respective roles of the fetus, estrogen, and progesterone on placental PAPP-A. Estradiol, progesterone, and PAPP-A concentrations were determined by RIA in maternal blood collected under ketamine anesthesia on Days 78-100 (n = 5), Days 102-144 (n = 4), and Days 146-164 (n = 3) of gestation (term = Day 184) in control baboons (Papio anubis) and on Days 110-164 in baboons fetectomized on Day 100 (n = 9). Studies were also conducted in five animals in which placental estrogen was increased by maternal treatment on Days 70-100 with androstenedione and in three animals treated on Days 140-164 with the antiestrogen, ethamoxytriphetol (MER-25; 25 mg/day/kg BW).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Influence of fetectomy on serum pregnancy-associated plasma protein-A concentrations in the baboon. 751 20

Different anaesthetic procedures that were used during an in vitro fertilisation and embryo transfer (IVF-ET) program have been analysed in order to determine their influence on plasma levels of estradiol, progesterone, prolactin, and beta-endorphin and results of IVF-ET. METHODS. Fifty-four patients awaiting transvaginal oocyte aspiration were randomised into three groups: (1) anaesthesia with ketamine as an induction agent and analgesic (n = 20); (2) general intubation anaesthesia using thiopentone for induction and enflurane for maintenance (n = 18); and (3) no anaesthesia (n = 16). Estradiol, progesterone, prolactin, and beta-endorphin were measured from day 3 to 14 referring to follicle aspiration. Differences between preoperative hormone levels and their intra- and postoperative peaks were analysed using the Kruskal-Wallis test (P < 0.03). The results were corrected using the Holms method (alpha = 0.05). RESULTS. No differences were observed in estradiol and progesterone levels (Figs. 1, 2). Prolactin levels were 1.4 times higher (P < 0.001) when ketamine was used and 2.2 times higher (P < 0.001) after short general anaesthesia than in the control group (Fig.3). Similar results were observed with respect to beta-endorphin: in comparison with the control group we found significant elevation by a factor of 2.1 when ketamine was used (P < 0.001). The discrepancy became even more marked with general anaesthesia: beta-endorphin was 3.9 times higher compared to the controls (P < 0.001) (Fig.4). Comparing the two groups who were given anaesthetics, prolactin and beta-endorphin levels were also significantly different (P < 0.001). The IVF procedure itself did not appear to be affected by different anaesthetic procedures during oocyte aspiration (Table 2). CONCLUSIONS. The increased prolactin and beta-endorphin plasma levels associated with ketamine and general anaesthesia reflect a significant alteration of the observed hormone levels. When anaesthesia is indicated, we try to avoid general intubation anaesthesia in favor of ketamine.
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PMID:[The effect of different anesthetic procedures on hormone levels in women. Studies during an in vitro fertilization-embryo transfer (IVF-ET) program]. 867 85

The present investigation was conducted to evaluate the effects of estradiol and progesterone on beta-endorphin and Met-enkephalin levels in specific brain regions of ovariectomized rats. Female Sprague-Dawley rats (100-120 g) adapted to a 12-hour light, 12-hour dark illumination cycle were used in these studies. Animals were ovariectomized under pentobarbital anesthesia. After a recovery period of 10-14 days, estradiol (50 micrograms/kg in 0.2 ml olive oil) was administered subcutaneously to rats at either 8.00, 14.00 or 16.00 h, progesterone (5 mg/kg in 0.1 ml olive oil) or estradiol plus progesterone was administered subcutaneously at 16.00 h. Control rats were injected with olive oil. Animals were sacrificed 2 h later. The cerebral cortex, hypothalamus, hippocampus and midbrain were dissected, and their beta-endorphin and Met-enkephalin levels were determined by radioimmunoassay. Estradiol administration at 8.00 h resulted in a significant decline in beta-endorphin levels of the hippocampus (66% decrease) and a significant rise in Met-enkephalin levels of the hypothalamus (37.8% increase) but had no effect on other brain regions studied. When estradiol was administered at 14.00 h, it produced a significant change in beta-endorphin levels in the cerebral cortex (34.7% increase) and in the midbrain (31.3% increase), but these levels were not altered in the other brain regions. At 16.00 h estradiol and progesterone alone caused a significant increase (29 and 43%, respectively) in beta-endorphin levels of the hippocampus. Similarly, the Met-enkephalin levels in the hippocampus significantly increased following administration of estradiol (57% increase) and progesterone (54% increase) alone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Diurnal variation in the acute effects of estradiol and progesterone on beta-endorphin and Met-enkephalin levels in specific brain regions of ovariectomized rats. 797 34


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