Regulation of CRH and AVP mRNA in the developing ovine hypothalamus: effects of stress and glucocorticoids

1995 ◽  
Vol 268 (6) ◽  
pp. E1096-E1107 ◽  
Author(s):  
S. G. Matthews ◽  
J. R. Challis

Developmental changes in the abundance, localization, and distribution of corticotropin-releasing hormone (CRH) mRNA and arginine vasopressin (AVP) mRNA in the ovine hypothalamus were examined by in situ hybridization. The effects of fetal hypoxemia in the presence or absence of concomitant cortisol in late gestation (day 135) were also investigated. CRH and AVP mRNA were present at low levels within the paraventricular nucleus (PVN) and AVP mRNA was present in the supraoptic nucleus (SON) by day 60 (full term = 147 days). During late gestation, there were increases (P < 0.05, days 140–143 vs. days 100–120) in CRH mRNA, a further increase (P < 0.05, full term vs. days 140–143) at full term (fetuses delivered in active labor), and a subsequent decline postpartum (compared with full term). AVP mRNA in the magnocellular PVN increased (P < 0.05) in late gestation, levels did not change in parvocellular fields compared with full term fetuses, but magnocellular and parvocellular AVP mRNA increased in the newborn (P < 0.05, newborn vs. full term). AVP mRNA in the SON showed a developmental profile similar to that of the PVN, although there was an increase earlier in gestation (P < 0.05, days 100–120 vs. days 60–80). Hypoxemia caused increases (P < 0.05) in CRH mRNA, plasma adrenocorticotropic hormone, and cortisol concentrations, and although magnocellular and parvocellular AVP mRNA appeared elevated, changes just failed to attain significance. Cortisol infusion attenuated the hypoxemia-induced increase in CRH mRNA and adrenocorticotropic hormone but was without effect on basal CRH mRNA levels.

1995 ◽  
Vol 144 (3) ◽  
pp. 483-490 ◽  
Author(s):  
S G Matthews ◽  
K Yang ◽  
J R G Challis

Abstract Developmental changes in pituitary glucocorticoid receptor (GR) mRNA were examined during gestation and early neonatal life using in situ hybridization. Pituitaries were harvested from sheep fetuses at days 60–80, 100–120, 130–135, 140–142 and term, and from lambs of days 0–7 and 30–60, and adults. GR mRNA was present in the pars distalis by day 60, levels increased through gestation, and there was a redistribution of GR mRNA, resulting in a relatively greater abundance at the base of the pars distalis. At term, there was a significant (P<0·05 compared with the day 140–142 fetuses) elevation of GR mRNA, which was maintained in the newborn lamb, reaching highest levels at days 30–60 of neonatal life. GR mRNA was undetectable in the pars intermedia until day 120, but subsequently increased to high levels at term. Interestingly, the expression of GR mRNA in the pars intermedia dropped precipitously in the newborn (P<0·05 compared with term), though levels recovered in the older lambs and adults. The regional and cellular distribution of GR mRNA correlated closely with the presence of immuno-reactive GR (irGR) in the pituitary; the majority of irGR was present in the nuclei. Intrafetal infusion of cortisol (12 h; 5 μg/min) in late gestation (day 135) had no effect on GR mRNA expression in either the pars distalis or pars intermedia. These results indicated that, in the fetal pituitary, (1) the GR gene is expressed in both the pars distalis and pars intermedia, (2) levels of GR mRNA in the fetal pituitary correlated with the distribution of nuclear irGR, (3) GR mRNA is present at higher levels in the inferior aspect of the pars distalis, its abundance increases immediately prior to parturition and is maintained in the newborn, and (4) cortisol infusion for 12 h does not affect GR mRNA in either region of the pituitary, suggesting that, in the short term, glucocorticoids do not directly regulate GR synthesis. Journal of Endocrinology (1995) 144, 483–490


Development ◽  
1989 ◽  
Vol 107 (3) ◽  
pp. 611-621 ◽  
Author(s):  
S.K. De ◽  
M.T. McMaster ◽  
S.K. Dey ◽  
G.K. Andrews

Oligodeoxyribonucleotide excess solution hybridization, Northern blot and in situ hybridization were used to analyze metallothionein gene expression in mouse decidua and placentae during gestation. Metallothionein (MT) -I and -II mRNA levels were constitutively elevated, 11- and 13-fold, respectively, relative to the adult liver, in the deciduum (D8), and decreased coordinately about 6-fold during the period of development when the deciduum is replaced by the developing placenta (D10-16). Coincident with this decline, levels of MT mRNA increased dramatically in the visceral yolk sac endoderm. In situ hybridization established that MT-I mRNA was present at low levels in the uterine luminal epithelium (D4), but was elevated at the site of embryo implantation exclusively in the primary decidual zone by D5, and then in the secondary decidual zone (D6-8). Although low levels of MT mRNA were detected in total placental RNA, in situ hybridization revealed constitutively high levels in the outer placental spongiotrophoblasts. Analysis of pulse-labeled proteins from decidua and placentae established that these tissues are active in the synthesis of MT. The constitutively high levels of MT mRNA in decidua were only slightly elevated following injection of cadmium (Cd) and/or zinc (Zn), whereas in placentae they increased several-fold. MT mRNA levels were equally high in decidua and experimentally induced deciduomata (D8) which establishes that decidual MT gene expression is not dependent on the presence of the embryo or some embryo-derived factor. Although the functional role of MT during development is speculative, these results establish the concept that, from the time of implantation to late in gestation, the mouse embryo is surrounded by cells, interposed between the maternal and embryonic environments, which actively express the MT genes. This suggests that MT plays an important role in the establishment and maintenance of normal pregnancy.


2000 ◽  
Vol 279 (4) ◽  
pp. R1239-R1250 ◽  
Author(s):  
Eric Glasgow ◽  
Takashi Murase ◽  
Bingjun Zhang ◽  
Joseph G. Verbalis ◽  
Harold Gainer

Magnocellular neurons of the hypothalamo-neurohypophysial system play a fundamental role in the maintenance of body homeostasis by secreting vasopressin and oxytocin in response to systemic osmotic perturbations. During chronic hyperosmolality, vasopressin and oxytocin mRNA levels increase twofold, whereas, during chronic hyposmolality, these mRNA levels decrease to 10–20% of that of normoosmolar control animals. To determine what other genes respond to these osmotic perturbations, we have analyzed gene expression during chronic hyper- versus hyponatremia. Thirty-seven cDNA clones were isolated by differentially screening cDNA libraries that were generated from supraoptic nucleus tissue punches from hyper- or hyponatremic rats. Further analysis of 12 of these cDNAs by in situ hybridization histochemistry confirmed that they are osmotically regulated. These cDNAs represent a variety of functional classes and include cytochrome oxidase, tubulin, Na+-K+-ATPase, spectrin, PEP-19, calmodulin, GTPase, DnaJ-like, clathrin-associated, synaptic glycoprotein, regulator of GTPase stimulation, and gene for oligodendrocyte lineage-myelin basic proteins. This analysis therefore suggests that adaptation to chronic osmotic stress results in global changes in gene expression in the magnocellular neurons of the supraoptic nucleus.


Reproduction ◽  
2016 ◽  
pp. 195-204 ◽  
Author(s):  
Qi-Tao Huang ◽  
Oksana Shynlova ◽  
Mark Kibschull ◽  
Mei Zhong ◽  
Yan-Hong Yu ◽  
...  

Uterine tissues contain the efflux transporter P-glycoprotein (P-gp, encoded by Abcb1a/1b gene), but little is known about how it changes through gestation. Our aim was to investigate the expression profile and cellular localization of P-gp in the pregnant, laboring and post-partum (PP) rat uterus. We propose that during pregnancy the mechanical and hormonal stimuli play a role in regulating myometrial Abcb1a/1b/P-gp. Samples from bilaterally and unilaterally pregnant rats were collected throughout gestation, during labor, and PP (n=4–6/gestational day). RNA and protein were isolated and subjected to quantitative PCR and immunoblotting; P-gp transcript and protein were localized by in situ hybridization and immunohistochemistry. Expression of Abcb1a/1b gene and membrane P-gp protein in uterine tissue (1) increased throughout gestation, peaked at term (GD19-21) and dropped during labor (GD23L); and (2) was upregulated only in gravid but not in empty horn of unilaterally pregnant rats. (3) The drop of Abcb1a/1b mRNA on GD23 was prevented by artificial maintenance of elevated progesterone (P4) levels in late gestation; (4) injection of the P4 receptor antagonist RU486 on GD19 caused a significant decrease in Abcb1 mRNA levels. (5) In situ hybridization and immunohistochemistry indicated that Abcb1/P-gp is absent from myometrium throughout gestation; (6) was expressed exclusively by uterine microvascular endothelium (at early gestation) and luminal epithelium (at mid and late gestation), but was undetectable during labor. In conclusion, ABC transporter protein P-gp in pregnant uterus is hormonally and mechanically regulated. However, its substrate(s) and precise function in these tissues during pregnancy remains to be determined.


1995 ◽  
Vol 147 (1) ◽  
pp. 139-146 ◽  
Author(s):  
S G Matthews ◽  
J R G Challis

Abstract It is well established that corticotrophin-releasing hormone and vasopressin can induce both synthesis and release of ACTH from the ovine pituitary gland, and that glucocorticoids can inhibit these responses. Changes in the abundance, localization and distribution of proopiomelanocortin (POMC) mRNA and prolactin (PRL) mRNA in the ovine fetal pituitary were examined by in situ hybridization following hypoxaemia applied in the presence or absence of concomitant cortisol in late gestation (day 135). Fetuses were distributed amongst four groups; saline-infused/normoxaemic, cortisol-infused/normoxaemic (0·3 mg/h), saline-infused/hypoxaemic and cortisol-infused/hypoxaemic. Hypoxaemia (6 h) was induced by reducing the maternal PaO2, resulting in a 6–8 mmHg decrease in fetal arterial PO2. Fetal infusions were commenced 5 h prior to and maintained throughout the treatment period. Hypoxaemia, which elevated fetal plasma ACTH and cortisol, caused a significant (P<0·05) increase in POMC mRNA in the pars distalis (PD), but was without effect on POMC mRNA in the pars intermedia (PI). Cortisol infusion attenuated the hypoxaemiainduced increase in POMC mRNA in the PD, but was without effect on non-stimulated steady-state POMC mRNA levels in either the PD or PI. PRL mRNA was only present in the PD and significantly (P<0·05) increased after cortisol infusion and hypoxaemia. In conclusion (i) POMC and PRL mRNA in the PD are increased following moderate hypoxaemia, (ii) cortisol attenuates changes in POMC mRNA but not PRL mRNA in the PD following hypoxaemia and (iii) cortisol increases PRL mRNA levels in the PD. Synthesis of POMC and PRL in the fetal PD is highly sensitive to homeostatic perturbations and glucocorticoids in late gestation. Journal of Endocrinology (1995) 147, 139–146


Endocrinology ◽  
1999 ◽  
Vol 140 (5) ◽  
pp. 2191-2198 ◽  
Author(s):  
Brenda N. Roy ◽  
Robert L. Reid ◽  
Dean A. Van Vugt

Abstract Ovarian steroids increase hypothalamic-pituitary-adrenal (HPA) axis activity and sensitize the hypothalamic-pituitary-ovarian (HPO) axis to stress-induced inhibition. The present study investigated the effect of ovarian steroids on CRH and arginine vasopressin (AVP) messenger RNA (mRNA) levels in the rhesus monkey hypothalamus, as both neuropeptides have been shown to stimulate the HPA axis and inhibit the HPO axis in this species. This was accomplished by measuring CRH and AVP mRNA in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) by in situ hybridization histochemistry. Menstrual cycles were simulated in ovariectomized (OVX) rhesus monkeys by sequential addition and removal of SILASTIC brand (Dow Corning Corp.) tubing containing either 17β-estradiol (E2) or progesterone (P4). On the morning of day 11 of the simulated follicular phase (E2 alone) or day 21 of the luteal phase (E2 + P4), animals were anesthetized, and the brains were perfused with paraformaldehyde via the carotid artery. Coronal sections (30 μm) were cut, and mRNA for CRH and AVP in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) were semiquantified by in situ hybridization. CRH mRNA in the PVN of E2-replaced OVX animals (n = 7) was 2-fold greater than that in untreated OVX controls (n = 4), whereas CRH mRNA after E2 + P4 (n = 4) was no different from that in controls (optical density ± sem, 0.38 ± 0.06, 0.13 ± 0.08, and 0.14 ± 0.09 for OVX + E2, OVX + E2 + P4, and OVX, respectively; P = 0.02). CRH in the SON was undetectable. In contrast to CRH, AVP mRNA in the PVN and the SON was similar in the three treatment groups. We conclude that E2 and E2 + P4 replacement to OVX monkeys exert different effects on CRH and AVP gene expression, as estrogen stimulation of CRH mRNA in the PVN was abrogated by progesterone, whereas no effect of ovarian steroids on AVP mRNA in either the PVN or SON was observed. We postulate that ovarian steroid regulation of CRH synthesis and release may in part explain the central nervous system mechanisms by which ovarian steroids affect the HPA and HPO axes during basal and stress conditions.


1992 ◽  
Vol 262 (3) ◽  
pp. E330-E337 ◽  
Author(s):  
K. Tavangar ◽  
Y. Murata ◽  
S. Patel ◽  
J. E. Kalinyak ◽  
M. E. Pedersen ◽  
...  

To evaluate changes in lipoprotein lipase (LPL) expression during development, levels of LPL mRNA, protein, and enzyme activity were measured in heart, epididymal fat, kidney, and brain of rats, from late gestation through 24 mo. LPL mRNA, protein, and enzyme activity were low in fetal and neonatal hearts. LPL mRNA increased 11-fold by 60 days and remained at this level thereafter; LPL protein and enzyme activity increased 10-fold by weaning, before declining to low values by 3 mo. LPL mRNA levels, protein, and enzyme activity did not change in epididymal fat from 3 wk to 21 mo. In the kidney, LPL mRNA levels were high at the end of gestation but fluctuated during the first month. LPL protein and activity were low at day 1 and rose eightfold to peak values by day 7 before decreasing to low levels by weaning. LPL mRNA levels were relatively high in fetal brains and then fell 60% during the neonatal period. LPL protein peaked at day 7 before falling 95% by weaning. Thus LPL is under complex tissue-specific regulation involving transcriptional and posttranscriptional mechanisms.


1988 ◽  
Vol 107 (2) ◽  
pp. 407-412 ◽  
Author(s):  
P Mali ◽  
M Sandberg ◽  
E Vuorio ◽  
P C Yelick ◽  
N B Hecht ◽  
...  

A mouse protamine 1 cDNA probe was used to study P1 protamine gene expression during the cycle of the seminiferous epithelium in the rat. In situ hybridization experiments showed that transcription of the P1 protamine mRNA starts in the middle of step 7 of spermiogenesis during substage VIIc. The mRNA levels stay high in steps 7-14 spermatids but decrease during steps 15-16 and are virtually undetectable in steps 17-19 spermatids. Northern blot analyses of RNAs isolated from microdissected pools of seminiferous tubules show high P1 protamine mRNA concentrations during stages VIIc-XIV-III of the cycle and lower levels during stages IV-VIIb. Owing to a post-transcriptional shortening of the poly(A) tail by 130 bases, a decrease in the size of protamine 1 mRNA from approximately 580 to 450 nucleotides was observed in stages XIII-XIV suggesting an initiation of protamine 1 synthesis in step 13-14 spermatids. In stages II-VI (steps 16-18 spermatids), only the smaller size protamine 1 mRNA was detectable. The expression of protamine 1 mRNAs has been localized in the very last phase of the haploid gene activity. Although the in situ hybridization suggests a disappearance of protamine 1 mRNA after step 16 of spermiogenesis, Northern blot analysis shows that low levels of mRNA are present during the period of final condensation of the chromatin, reflecting the association of protamine with DNA.


Reproduction ◽  
2005 ◽  
Vol 130 (2) ◽  
pp. 241-250 ◽  
Author(s):  
L S Hartt ◽  
S J Carling ◽  
M M Joyce ◽  
G A Johnson ◽  
D K Vanderwall ◽  
...  

Uterine function is primarily controlled by the combined actions of oestrogen and progesterone working through their cognate nuclear receptors. The mechanism of establishment of pregnancy in the mare is of interest because it involves prolonged pre-attachment and conceptus migration phases, and both invasive and non-invasive placental cell types, and as such has been an important comparative model. This study characterised regulation of oestrogen (ER) and progesterone (PR) receptors in the endometrium of the mare during the oestrous cycle and early pregnancy. Endometrial tissues collected during the oestrous cycle and early pregnancy were analysed for steady-state levels of ER and PR mRNA and protein. Steady-state levels of ER and PR mRNA were highest on days 0, 17 and 20 in cyclic mares and lowest on days 11 and 14. A day-by-status interaction was detected, indicating that day 17 and day 20 pregnant mares exhibited low levels of ER and PR compared with the corresponding days of the oestrous cycle. In situ hybridisation analyses showed receptor mRNA localisation primarily in the luminal epithelium (LE), glandular epithelium (GE) and stroma around oestrus. During dioestrus and early pregnancy, receptors were not detected in the LE, and were lower in the stroma and deeper GE. Changes in hybridisation intensity in these cell types were consistent with changes in mRNA levels detected by slot-blot hybridisation. ER and PR proteins were detected in the nuclei of LE, GE and stromal cells. Consistent with results from in situ hybridisation, levels of ER and PR immunoreactivity were higher around oestrus, declined to low levels during dioestrus and remained low during early pregnancy. Results described here for temporal and spatial changes in steroid receptor gene expression in mares show the greatest similarities with those described for cattle and sheep.


1994 ◽  
Vol 13 (2) ◽  
pp. 175-185 ◽  
Author(s):  
S G Matthews ◽  
X Han ◽  
F Lu ◽  
J R G Challis

ABSTRACT Ontogenic changes in pituitary pro-opiomelanocortin (POMC) mRNA and prolactin (PRL) mRNA were examined during gestation and early neonatal life using in situ hybridization histochemistry. Pituitaries were harvested from fetuses at days 60–80, 100–120, 135–140 and 142–143 of gestation and at term, and from lambs at days 1–7 and 30–60 of age and adults. POMC mRNA, present by day 60, rose during mid- and late gestation. Concurrently there was a change in corticotroph distribution, resulting in a relatively greater quantity of POMC mRNA at the base of the pars distalis. At term, there was a significant (P<0·05) further elevation of POMC mRNA. POMC mRNA levels remained high in the newborn lamb but decreased in the adult. Cells in the pars intermedia expressed large amounts of POMC mRNA early in fetal life and this pattern persisted throughout gestation and into the neonatal period. Changes in the expression of the POMC gene correlated closely with the presence of immunoreactive (ir)ACTH in the pituitary; in fetuses the proportion of irACTH-positive cells rose to 10% of pars distalis cells by day 100 and did not change significantly thereafter. The lactotrophs contained PRL mRNA by day 60, and the quantity increased towards parturition (P<0·05). PRL mRNA subsequently decreased in the neonate, but rose as the lamb matured. These results indicate that in the fetal pituitary: (1) the POMC gene is highly expressed during gestation in both the pars distalis and the pars intermedia, (2) changes in the amounts of POMC mRNA and PRL mRNA in the pars distalis correlate with the distribution of irACTH and irPRL respectively, and (3) POMC mRNA is distributed primarily in the inferior aspect of the pars distalis, and in this region its quantity is highest immediately prior to parturition.


Sign in / Sign up

Export Citation Format

Share Document