Matthews S G, Challis J R
Lawson Research Institute, Medical Research Council Group in Fetal and Neonatal Health and Development, University of Western Ontario, St. Joseph's Health Centre, London, Canada.
Am J Physiol. 1995 Jun;268(6 Pt 1):E1096-107. doi: 10.1152/ajpendo.1995.268.6.E1096.
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.
通过原位杂交技术检测了绵羊下丘脑促肾上腺皮质激素释放激素（CRH）mRNA和精氨酸加压素（AVP）mRNA的丰度、定位及分布的发育变化。同时研究了妊娠晚期（第135天）存在或不存在伴随皮质醇时胎儿低氧血症的影响。到第60天（足月为147天）时，室旁核（PVN）内CRH和AVP mRNA水平较低，视上核（SON）内有AVP mRNA。在妊娠晚期，CRH mRNA增加（P<0.05，第140 - 143天与第100 - 120天相比），足月时（活跃分娩时娩出的胎儿）进一步增加（P<0.05，足月与第140 - 143天相比），产后随后下降（与足月相比）。大细胞性PVN中的AVP mRNA在妊娠晚期增加（P<0.05），与足月胎儿相比，小细胞区域水平未变化，但新生羊中大细胞和小细胞AVP mRNA增加（P<0.05，新生羊与足月相比）。SON中的AVP mRNA显示出与PVN相似的发育模式，尽管在妊娠早期增加（P<0.05，第100 - 120天与第60 - 80天相比）。低氧血症导致CRH mRNA、血浆促肾上腺皮质激素和皮质醇浓度增加（P<0.05），虽然大细胞和小细胞AVP mRNA似乎升高，但变化未达到显著水平。皮质醇输注减弱了低氧血症诱导的CRH mRNA和促肾上腺皮质激素增加，但对基础CRH mRNA水平无影响。
