Journal of Endocrinology (J ENDOCRINOL)
Journal of Endocrinology provides a wide coverage of research in all aspects of endocrinology. It is in the top ranks of global endocrine journals and publishes high quality, leading-edge research from all over the world. The readership of the journal is worldwide, with 40% of readers in North America. Most issues contain a review article or commentary on a topical subject. These have been well received and are highly cited. There is also a fast track rapid communications system which means that exceptional papers can be published in as little as six weeks from receipt.
- Impact factor3.55Show impact factor historyHide impact factor history
- WebsiteJournal of Endocrinology website
Other titlesJournal of endocrinology
Material typePeriodical, Internet resource
Document typeJournal / Magazine / Newspaper, Internet Resource
- Author cannot archive a pre-print version
- Author cannot archive a post-print version
- 12 months embargo
- Publisher copyright and source must be acknowledged
- Authors accepted manuscript must carry a set statement (see policy)
- On a non-profit server
- Publishers version/PDF can not be used unless payment of Open Access Option fee is made (Publisher will deposit final PDF automatically on payment to PubMed Central)
- Open Access Option must be used if there is a mandate by institution or funding body to deposit before 12 months after publication.
Publications in this journal
Article: 4. Li M, Leatherland JF, Vijayan M, King WA, Madan P. 2012. In Ovo Elevated Oocyte Cortisol Content Stimulates Early Rainbow Trout Embryo Cell Division By the Activation of Glucocorticoid Receptors. Journal of Endocrinology. 215:137-149. doi: 10.1530/JOE-12-0030.Journal of Endocrinology 08/2012; 215:137-149.
Journal of Endocrinology 08/2012;
Article: Reactive oxygen and nitrogen species generation, antioxidant defenses and β-cell function: a critical role for amino acidsJournal of Endocrinology 04/2012;
Article: The effect of nutrition on the neural mechanisms potentially involved in melatonin-stimulated LH secretion in female Mediterranean goats[show abstract] [hide abstract]
ABSTRACT: This research examines which neural mechanisms among the endogenous opioid, dopaminergic, serotonergic and excitatory amino acid systems are involved in the stimulation of LH secretion by melatonin implantation and their modulation by nutritional level. Female goats were distributed to two experimental groups that received either 1.1 (group H; n=24) or 0.7 (group L; n=24) times their nutritional maintenance requirements. Half of each group was implanted with melatonin after a long-day period. Plasma LH concentrations were measured twice per week. The effects of i.v. injections of naloxone, pimozide, cyproheptadine and N-methyl-D,L-aspartate (NMDA) on LH secretion were assessed the day before melatonin implantation and again on days 30 and 45. The functioning of all but the dopaminergic systems was clearly modified by the level of nutrition, melatonin implantation and time elapsed since implantation. Thirty days after implantation, naloxone increased LH concentrations irrespective of the level of nutrition (P<0.05), similar to NMDA in the melatonin implanted H goats (HM; P<0.01). On day 45, naloxone increased LH concentrations in the HM animals (P<0.05), similar to cyproheptadine in both the non-implanted H (HC) and the HM animals (P<0.01). Finally, at 45 days, NMDA increased the LH concentration in all subgroups (P<0.01). These results provide evidence that the effects of different neural systems on LH secretion are modified by nutritional level and melatonin implantation. Endogenous opioids seem to be most strongly involved in the inhibition of LH secretion on days 30 and 45 after melatonin implantation. However, the serotonergic mechanism appears to be most influenced by nutritional level.Journal of Endocrinology 01/2011; 211:263-272.
Article: Signal transducer and activator of transcription 3-regulated sarcoendoplasmic reticulum Ca2+-ATPase 2 expression by prolactin and glucocorticoids is involved in the adaptation of insulin secretory response during the peripartum period.[show abstract] [hide abstract]
ABSTRACT: During pregnancy, the maternal endocrine pancreas undergoes, as a consequence of placental lactogens and prolactin (PRL) action, functional changes that are characterized by increased glucose-induced insulin secretion. After delivery, the maternal endocrine pancreas rapidly returns to non-pregnant state, which is mainly attributed to the increased serum levels of glucocorticoids (GCs). Although GCs are known to decrease insulin secretion and counteract PRL action, the mechanisms for these effects are poorly understood. We have previously demonstrated that signal transducer and activator of transcription 3 (STAT3) is increased in islets treated with PRL. In the present study, we show that STAT3 expression and serine phosphorylation are increased in pancreatic islets at the end of pregnancy (P19). STAT3 serine phosphorylation rapidly returned to basal levels 3 days after delivery (L3). The expression of the sarcoendoplasmic reticulum Ca(2+)-ATPase 2 (SERCA2), a crucial protein involved in the regulation of calcium handling in beta-cells, was also increased in P19, returning to basal levels at L3. PRL increased SERCA2 and STAT3 expressions and STAT3 serine phosphorylation in RINm5F cells. The upregulation of SERCA2 by PRL was abolished after STAT3 knockdown. Moreover, PRL-induced STAT3 serine phosphorylation and SERCA2 expression were inhibited by dexamethasone (DEX). Insulin secretion from islets of P19 rats pre-incubated with thapsigargin and L3 rats showed a dramatic suppression of first phase of insulin release. The present results indicate that PRL regulates SERCA2 expression by a STAT3-dependent mechanism. PRL effect is counteracted by DEX and might contribute to the adaptation of maternal endocrine pancreas during the peripartum period.Journal of Endocrinology 11/2007; 195(1):17-27.
Article: Benign prostatic hyperplasia (BPH) epithelial cell line BPH-1 induces aromatase expression in prostatic stromal cells via prostaglandin E2.[show abstract] [hide abstract]
ABSTRACT: Estradiol (E2) level in stroma of benign prostatic hyperplasia (BPH) increases with age, and this increase was associated with an elevated expression of aromatase in prostatic stromal cells (PrSCs). Here, we showed that conditioned medium (CM) of BPH-1 (a benign hyperplastic prostatic epithelial cell line), but not of prostate cancer cell lines (LNCaP, DU-145, and PC-3), stimulates aromatase expression in PrSCs. Cyclooxygenase-2 (COX-2) mRNA level in BPH-1, as well as prostaglandin E2 (PGE2) concentration in BPH-1 CM, was significantly higher than that of prostate cancer cell lines. CM of BPH-1 treated with NS-398 (a specific inhibitor of COX-2) failed to stimulate aromatase expression in PrSCs. And PGE2 can stimulate aromatase expression in PrSCs. Our data suggested that BPH-1 induced aromatase expression in PrSCs through the production of PGE2 in a paracrine mechanism.Journal of Endocrinology 11/2007; 195(1):89-94.
Article: Non-esterified fatty acids and human lymphocyte death: a mechanism that involves calcium release and oxidative stress.[show abstract] [hide abstract]
ABSTRACT: Although previous studies have shown that a mixture of fatty acids in similar proportion to that found in human plasma triggers apoptosis of peripheral blood lymphocytes from healthy subjects, the mechanism involved remains unknown. In the present study, we examined whether the effect of a mixture of fatty acids upon human lymphocyte death involves cytochrome c release from the mitochondria, activation of caspases 3, 6, 8, and 9, production of superoxide anion, nitric oxide (NO), increase in cytosolic Ca(2+) levels, and expression of the anti-apoptotic 14-3-3 and the pro-apoptotic FasL, bad, and bid proteins. Peripheral blood lymphocytes from healthy subjects were isolated and treated for up to 48 h with increasing concentrations (0.1-0.4 mM) of the fatty acid mixture. Cells were then harvested and thecytochromec release from mitochondrial intermembrane space into cytosol and expression of anti- and pro-apoptotic proteins were investigated by western blot analysis. Activities of caspases 3, 6, 8, and 9 were determined using spectrofluorometric assays. NO production was monitored using DAF-2-FM probe. Cytosolic free calcium concentration ([Ca(2+)](i)) was determined using the fluorescent probe Fura-2-AM. Superoxide anion was assayed using lucigenin and dihydroethidine assays. Lymphocytes treated for 24 h with the fatty acid mixture presented increased cytochrome c release from mitochondria as compared with control lymphocytes without treatment. Activities of caspases 3, 6, and 9 were increased by 146, 22 and 35% respectively by the treatment with 0.4 mM concentration of the fatty acid mixture for 24 h. The expression of bid protein was significantly increased in lymphocytes by 40% at 0.2 mM and by 80% at 0.4 mM fatty acid concentration, whereas FasL, 14-3-3 and bad proteins were not affected by the treatment. Intracellular calcium concentration was increased in a dose-dependent manner after 30 min of fatty acid treatment and addition of BSA (0.2%) abolished this increase. Production of NO and superoxide anion was also increased by the fatty acid mixture and BSA loaded in the culture medium prevented this increase. In conclusion, fatty acids induced apoptosis of human lymphocytes by a mechanism that involved cytochrome c release from mitochondria, activation of the caspase cascade, and increase of bid protein content, superoxide and NO production, and of cytosolic calcium concentration.Journal of Endocrinology 11/2007; 195(1):133-43.
[show abstract] [hide abstract]
ABSTRACT: The post-translational processing of the TSH receptor (TSHR) includes intra-molecular cleavage with the loss of a 50 amino acid ectodomain region and the formation of two subunits (alpha and beta), followed by likely alpha subunit shedding. TSHR antibodies (TSHR-Abs), which are directed at the ectodomain, may influence thyroid function by stimulating or inhibiting TSHR signaling or may bind without any such influence (the neutral group of antibodies). When we examined the characteristics of a series of monoclonal TSHR-Abs, we found that many were able to inhibit receptor cleavage and enhance TSHR expression. This was especially apparent with the neutral type of TSHR-Abs directed to the cleaved region of the ectodomain (aa 316-366). Indeed, such inhibition appeared to be epitope dependent with TSHR-Abs directed to regions after residues 335-354 showing no such activity. We propose that this aberrant process, whereby TSHR-Abs influence antigen processing, is a novel mechanism for the maintenance and exacerbation of autoimmune thyroid disease.Journal of Endocrinology 11/2007; 195(1):179-86.
Article: Cross-regulation of cortisol secretion by adrenocorticotropin and platelet-activating factor in perfused guinea pig adrenals.[show abstract] [hide abstract]
ABSTRACT: We examined the cross-regulation of signaling between ACTH-and platelet-activating factor (PAF)-mediated steroidogenesis in the perfused guinea pig adrenal gland. Our method of in situ perfusion using an artificial medium can evaluate whether cortisol secretion in response to ACTH and PAF is interactive. Treating adrenal glands with 100 pg/ml ACTH diminished the subsequent cortisol response to 10 nM PAF. By contrast, PAF resulted in subsequent potentiation of ACTH-induced cortisol secretion. A mixture of 50 microM L-alpha-1-oleoyl-2-acetyl-sn-glycerol (OAG), an activator of protein kinase C (PKC), and 3.3 microM calcium ionophore (A23187), or 10 microM forskolin (FRK) diminished the cortisol response to PAF, whereas that to ACTH was unaffected. Each of PAF, ACTH, or FRK eliminated the cortisol response to OAG plus A23187, whereas that to FRK was unaffected. These data show that the protein kinase A (PKA)-dependent processes activated by ACTH or FRK can interfere with PAF-induced signal transduction at receptor and post-receptor levels. In contrast, PKC-dependent processes activated by PAF promoted ACTH-signaling at receptor and post-receptor level. Cross-regulation between processes activated by PAF receptor-PKC and by ACTH receptor-PKA might function in the multifactorial regulation of adrenocortical steroidogenesis.Journal of Endocrinology 11/2007; 195(1):29-38.
Article: Fetal programming of colon cancer in adult rats: correlations with altered neonatal growth trajectory, circulating IGF-I and IGF binding proteins, and testosterone.[show abstract] [hide abstract]
ABSTRACT: We examined effects of dietary soy protein isolate (SPI) or genistein (GEN; soy isoflavone) during pregnancy on development of colon cancer in male progeny Sprague-Dawley rats. Four groups of rats were used: a lifetime casein-fed group (CAS; control diet), a lifetime SPI-fed group (positive control for protective effect of diet on colon carcinogenesis), a group whose dams received SPI only during pregnancy and CAS thereafter (SPI/CAS), and a group whose dams received CAS+GEN only during pregnancy and CAS thereafter (GEN/CAS). At 47 and 55 days of age, male progeny were administered the intestinal carcinogen azoxymethane (AOM). Tumors, endocrine status, and colon gene expression were evaluated at 20 week post-AOM. The SPI group had 47% decreased colon tumor incidence compared with the CAS group (P<0.05), whereas SPI/CAS, GEN/CAS, and CAS groups did not differ in this regard. Maternal-only SPI increased the percentage of animals bearing multiple colon tumors (P<0.05), an effect not mimicked by GEN. Serum insulin and leptin concentrations were decreased by lifetime SPI (P<0.05), whereas serum IGF-I was elevated in the SPI/CAS group (P<0.05). The SPI/CAS group had reduced serum testosterone levels (P<0.05) and exhibited a tendency for increased mucosal expression of IGF-I receptor and glucose transporter-1 mRNAs. Results indicate an effect of dietary protein type during pregnancy on colon tumor multiplicity and colon tissue gene expression, and serum IGF-I and testosterone in progeny rats as later adults.Journal of Endocrinology 11/2007; 195(1):79-87.
Article: Glucocorticoid-induced apoptosis in human decidua: a novel role for 11beta-hydroxysteroid dehydrogenase in late gestation.[show abstract] [hide abstract]
ABSTRACT: Glucocorticoids play a fundamental role in the endocrinology of pregnancy but excess glucocorticoids in utero may lead to abnormalities of fetal growth. Protection against fetal exposure to cortisol is provided by the enzyme 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) located in the human placental trophoblast. By contrast, relatively little is known concerning the function of glucocorticoid-activating 11beta-HSD1, which is strongly expressed within human maternal decidua. To address this we have assessed: i) changes in decidual 11beta-HSD1 expression across gestation and ii) the functional role of glucocorticoids in decidua. Human decidua was collected from women undergoing surgical termination of pregnancy in first (n = 32) and second (n = 10) trimesters, and elective caesarean sections in the third trimester (n = 9). Analysis of mRNA for 11beta-HSD1 by real-time RT-PCR showed increased expression in second (9.3-fold, P < 0.01) and third (210-fold, P < 0.001) trimesters. Studies using primary cultures of decidual cells also revealed higher levels of cortisol generation in the third trimester. Changes in decidual 11beta-HSD1 with gestation were paralleled by increased expression of the apoptosis markers caspase-3 and annexin-V, particularly in cluster designation (CD)10(-VE) non-stromal cells (20-fold in third trimester relative to first trimester). Apoptosis was also readily induced in primary cultures of third trimester decidual cells when treated with cortisol, cortisone, or dexamethasone (all 100 nM for 24 h). The effect of cortisone but not cortisol or dexamethasone was blocked by an 11beta-HSD inhibitor confirming the functional significance of endogenous cortisol generation. These data show that autocrine metabolism of glucocorticoids is an important facet of the feto-placental unit in late gestation and we propose that a possible effect of this is to stimulate programmed cell death in human decidua.Journal of Endocrinology 11/2007; 195(1):7-15.
[show abstract] [hide abstract]
ABSTRACT: CXC chemokine ligand 10 (CXCL10) plays a pivotal role in the self-perpetuation of the inflammatory processes in patients with autoimmune thyroid disease. Treatment with methimazole (MMI) reduces serum CXCL10 in patients with Graves' disease. In isolated human thyrocytes, tumor necrosis factor (TNF)alpha demonstrates a potent synergistic effect on interferon (IFN)gamma-induced CXCL10 secretion. We investigated the mechanism underlying the synergism between IFNgamma and TNFalpha and the effect of MMI on CXCL10 secretion in human thyrocytes. A peroxisome proliferator-activated receptor gamma agonist, rosiglitazone (RGZ), a known inhibitor of T helper 1 (Th1)-mediated responses, was also studied for comparison. Experiments were carried out in human thyrocytes isolated from internodular parenchyma of thyroid tissues derived from patients who had undergone surgery for multinodular goiter. ELISA was used to measure CXCL10 levels in culture supernatant. Flow cytometry was used to assess IFNgamma membrane receptor expression. Specific mRNA analysis was performed by Taqman real-time PCR. Immunofluorescence was performed to detect nuclear translocation of nuclear factor-kappaB (NF-kappaB). In human thyrocytes, the synergistic effect of TNFalpha with IFNgamma on CXCL10 secretion is due to the upregulation of IFNgamma receptor expression. MMI decreased cytokine-induced CXCL10 secretion by reducing TNFalpha-induced upregulation of the IFNgamma receptor. RGZ decreased the cytokine-induced CXCL10 secretion by impairing NF-kappaB translocation, without affecting IFNgamma receptor. MMI and RGZ targeted thyrocytes with the same pharmacological potency, likely acting throughout different mechanisms. Targeting T helper 1-mediated autoimmune thyroid disease with drugs that impair different intracellular pathways could be a novel pharmacological tool.Journal of Endocrinology 11/2007; 195(1):145-55.
Article: Ciliary neurotrophic factor promotes survival of neonatal rat islets via the BCL-2 anti-apoptotic pathway.[show abstract] [hide abstract]
ABSTRACT: Ciliary neurotrophic factor (CNTF) belongs to the cytokine family and increases neuron differentiation and/or survival. Pancreatic islets are richly innervated and express receptors for nerve growth factors (NGFs) and may undergo neurotypic responses. CNTF is found in pancreatic islets and exerts paracrine effects in neighboring cells. The aim of this study was to investigate possible effects of CNTF on neonatal rat pancreatic islet differentiation and/or survival. For this purpose, we isolated pancreatic islets from neonatal rats (1-2 days old) by the collagenase method and cultured for 3 days in RPMI medium with (CNTF) or without (CTL) 1 nM CNTF. Thereafter, glucose-stimulated insulin secretion (RIA), general metabolism by (NAD(P)H production; MTS), glucose metabolism ((14)CO(2) production), gene (RT-PCR), protein expression (western blotting), caspase-3 activity (Asp-Glu-Val-Asp (DEVD)), and apoptosis (DNA fragmentation) were analyzed. Our results showed that CNTF-treated islets demonstrated reduced glucose-induced insulin secretion. CNTF treatment did not affect glucose metabolism, as well as the expression of mRNAs and proteins that are crucial for the secretory process. Conversely, CNTF significantly increased mRNA and protein levels related to cell survival, such as Cx36, PAX4, and BCL-2, reduced caspase-3 activity, and islet cells apoptosis, suggesting that CNTF does not affect islet cell differentiation and, instead, acts as a survival factor reducing apoptosis by increasing the expression of the anti-apoptotic BCL-2 protein and decreasing caspase-3 activity.Journal of Endocrinology 11/2007; 195(1):157-65.
Article: Pro-inflammatory cytokines increase glucose, alanine and triacylglycerol utilization but inhibit insulin secretion in a clonal pancreatic beta-cell line.[show abstract] [hide abstract]
ABSTRACT: We have investigated the effects of prolonged exposure (24 h) to pro-inflammatory cytokines on beta-cell metabolism and insulin secretion using clonal BRIN-BD11 beta cells. Addition of IL-1beta, tumour necrosis factor-alpha and IFN-gamma (at concentrations that did not induce apoptosis) inhibited chronic (24 h) and acute stimulated levels of insulin release (by 59 and 93% respectively), increased cellular glucose and alanine consumption, and also elevated lactate and glutamate release. However, ATP levels and cellular triacylglycerol were decreased while glutathione was increased. We conclude that sub-lethal concentrations of pro-inflammatory cytokines appear to shift beta-cell metabolism away from a key role in energy generation and stimulus-secretion coupling and towards a catabolic state which may be related to cell defence.Journal of Endocrinology 11/2007; 195(1):113-23.
Article: Recurrence of the p.R277X/p.R1511X compound heterozygous mutation in the thyroglobulin gene in unrelated families with congenital goiter and hypothyroidism: haplotype analysis using intragenic thyroglobulin polymorphisms.[show abstract] [hide abstract]
ABSTRACT: Thyroglobulin (TG) functions as the matrix for thyroid hormone synthesis. Thirty-five different loss-of-function mutations in the TG gene have been reported. These mutations are transmitted in an autosomal recessive mode. The objective of this study is to analyze the recurrence of the p.R277X/p.R1511X compound heterozygous mutation in the TG gene in two unrelated families (one Argentinian and another Brazilian) with congenital hypothyroidism, goiter and impairment of TG synthesis. The first and last exon of the TG gene, the exons where previously mutations and single nucleotide polymorphisms (SNPs) were detected, as well as the TG promoter, were analyzed by automatic sequencing in one affected member of the each family. Four microsatellite markers localized in introns 10, 27, 29 and 30 of the TG gene, one insertion/deletion intragenic polymorphism and 15 exonic SNPs were used for haplotype analysis. A p.R277X/p.R1511 compound heterozygous mutation in the TG gene was found in two members of an Argentinian family. The same mutations had been also reported previously in two members of a Brazilian family. We constructed mutation-associated haplotypes by genotyping members of the two families. Our results suggest that the cosegregating haplotype is different in each one of these families. Different haplotypes segregated with the p.R277X and p.R1511 mutations demonstrating the absence of a founder effect for these mutations between Argentinian and Brazilian populations. However, haplotyping of Argentinian patients showed the possibility that the p.R277X alleles might be derived from a common ancestral chromosome.Journal of Endocrinology 11/2007; 195(1):167-77.
[show abstract] [hide abstract]
ABSTRACT: The year 1946 was not only the year that the Society for Endocrinology was founded, but also the year that Edward Kendall's compound E (cortisone) was first synthesised by Louis Sarett. By 1948, sufficient quantities of compound E were available for the rheumatologist Philip Hench to test it successfully for the first time in a patient with rheumatoid arthritis. It was immediately hailed as a 'wonder drug' and was shown to be effective in a number of inflammation-associated conditions, most notably rheumatoid arthritis. The subsequent development of endocrinology as a discipline is inextricably linked to the chemistry, biology and medicine of antiinflammatory glucocorticoids. Sixty years after the first chemical synthesis of cortisone, corticosteroids remain among the top ten most commonly used prescription and over the counter drugs. Basic and clinical studies of glucocorticoid biosynthesis, metabolism and action have trail-blazed developments in endocrinology ever since. This article surveys the extraordinary cortisone timeline, from first synthesis until now. The concluding scientific message is that intracrine metabolism of cortisone to cortisol via 11beta hydroxysteroid dehydrogenase type 1 likely sustains local amplification of glucocorticoid action at sites of inflammation throughout the body. The broader message is that the discovery of compound E by Kendall (basic scientist), its large-scale synthesis by Sarett (industrial chemist) and its therapeutic application by Hench (rheumatologist) serves as a paradigm for modern translational medicine. It is concluded that endocrinology will remain a force in health and disease if it continues to evolve sans frontières at the basic/applied/clinical science interface. A challenge for the Society for Endocrinology is to ensure this happens.Journal of Endocrinology 11/2007; 195(1):1-6.
Article: G-protein-coupled receptors in aldosterone-producing adenomas: a potential cause of hyperaldosteronism.[show abstract] [hide abstract]
ABSTRACT: The source of aldosterone in 30-40% of patients with primary hyperaldosteronism (PA) is unilateral aldosterone-producing adenoma (APA). The mechanisms causing elevated aldosterone production in APA are unknown. Herein, we examined the expression of G-protein-coupled receptors (GPCRs) in APA and demonstrated that when compared with normal adrenals, there is a general elevation of certain GPCR in many APA and/or ectopic expression of GPCR in others. RNA samples from normal adrenals (n = 5), APAs (n = 10), and cortisol-producing adenomas (CPAs; n = 13) were used on 15 genomic expression arrays, each of which included 223 GPCR transcripts presented in at least 1 out of 15 of the independent microarrays. The array results were confirmed using real-time RT-PCR (qPCR). Four GPCR transcripts exhibited a statistically significant increase that was greater than threefold when compared with normal adrenals, suggesting a general increase in expression when compared with normal adrenal glands. Four GPCR transcripts exhibited a > 15-fold increase of expression in one or more of the APA samples when compared with normal adrenals. qPCR analysis confirmed array data and found the receptors with the highest fold increase in APA expression to be LH receptor, serotonin receptor 4, GnRH receptor, glutamate receptor metabotropic 3, endothelin receptor type B-like protein, and ACTH receptor. There are also sporadic increased expressions of these genes in the CPAs. Together, these findings suggest a potential role of altered GPCR expression in many cases of PA and provide candidate GPCR for further study.Journal of Endocrinology 11/2007; 195(1):39-48.
Article: Relationships of circulating pregnanolone isomers and their polar conjugates to the status of sex, menstrual cycle, and pregnancy.[show abstract] [hide abstract]
ABSTRACT: Pregnanolone isomers (PIs) and their polar conjugates (PICs) modulate ionotropic receptors such as gamma-aminobutyric acid or pregnane X receptors. Besides, brain synthesis, PI penetrates the blood-brain barrier. We evaluated the physiological importance of PI respecting the status of sex, menstrual cycle, and pregnancy. Accordingly, circulating levels of allopregnanolone (P3alpha 5alpha ), isopregnanolone (P3beta 5alpha ), pregnanolone (P3alpha 5beta ), epipregnanolone (P3beta 5beta ), their polar conjugates, and related steroids were measured in 15 men (M), 15 women in the follicular phase (F), 16 women in the luteal phase (L), and 30 women in the 36th week of gestation (P) using GC-MS. The steroid levels were similar in M and F, increased about thrice in L and escalated in P (38-410 times compared with F). The PICs were prevalent over the PIs (16-150 times). Higher ratios of 5alpha-PIC to 5alpha-PI found in P indicate the more intensive conjugation of 5alpha-PI during pregnancy. This mechanism probably provides for the elimination of neuroinhibitory P3alpha 5alpha in the maternal compartment. Additionally, our result points to a limited sulfation capacity for neuroinhibitory P3alpha 5beta in P. In contrast to the situation in M, F, and L where the P3alpha 5beta C is the most abundant PIC, and P3alpha 5beta is present in minor quantities compared with the P3alpha 5alpha, P3alpha 5beta may acquire physiological importance during pregnancy, contributing to the sustaining thereof. On the other hand, the declining formation of P3alpha 5beta may participate in the initiation of parturition, given the relative abundance of the steroid, its potency to suppress the activity of oxytocin-producing cells and its effectiveness in uterine relaxation.Journal of Endocrinology 11/2007; 195(1):67-78.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.
ISSN: 1873-2399, Impact factor: 3.11
New York Academy of Sciences;...
ISSN: 1749-6632, Impact factor: 3.15
John Wiley & Sons
ISSN: 1098-1128, Impact factor: 10.7
ISSN: 0954-6820, Impact factor: 5.48
International Society for the Study...
ISSN: 0952-3278, Impact factor: 3.37
John Wiley & Sons
ISSN: 0899-1987, Impact factor: 3.16