Cerebrospinal fluid and plasma concentrations of oxytocin and vasopressin during parturition and vaginocervical stimulation in the sheep

Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli.     

胸腰椎压缩性骨折的护理要点

胸腰椎压缩性骨折的护理要点福建漳州市中医院（３６３０００）郭燕玲，陈联源我院自１９８９年来对胸腰椎压缩性骨折实行辨证护理，收到满意效果，介绍如下。常规护理：屈曲型胸腰椎压缩性骨折，令病人仰卧在硬板床上，骨折处垫一软枕头，在耐受的情况下逐渐增加枕头高度...     

Intracerebroventricular injection of choline increases plasma oxytocin levels in conscious rats

In the present study, we examined the effect of intracerebroventricularly (i.c.v.) injected choline on both basal and stimulated oxytocin release in conscious rats. I.c.v. injection of choline (50–150 μg) caused time- and dose-dependent increases in plasma oxytocin levels under normal conditions. The increase in plasma oxytocin levels in response to i.c.v. choline (150 μg) was greatly attenuated by the pretreatment of rats with atropine (10 μg; i.c.v.), muscarinic receptor antagonist. Mecamylamine (50 μg; i.c.v.), a nicotinic receptor antagonist, failed to suppress the effect of 150 μg choline on oxytocin levels. Pretreatment of rats with 20 μg of hemicholinium-3 (HC-3), a specific inhibitor of choline uptake into nerve terminals, greatly attenuated the increase in plasma oxytocin levels in response to i.c.v. choline injection. Osmotic stimuli induced by either oral administration of 1 ml hypertonic saline (3 M) following 24-h dehydration of rats (type 1) or an i.c.v. injection of hypertonic saline (1 M) (type 2) increased plasma oxytocin levels significantly, but hemorrhage did not alter basal oxytocin concentrations. The i.c.v. injection of choline (50, 150 μg) under these conditions caused an additional and significant increase in plasma oxytocin concentrations beyond that produced by choline in normal conditions. These data show that choline can increase plasma oxytocin concentrations through the stimulation of central cholinergic muscarinic receptors by presynaptic mechanisms and enhance the stimulated oxytocin release.     

The Recognition of Hypothalamo-Neurohypophysial Functions by Developing T Cells

Neuropeptide signals and specific neuropeptide receptors have been described in the thymus supporting the concept of a close dialogue between the neuroendocrine and the immune systems at the level of early T-cell differentiation. In this paper, we review recent data about neurohypophysial (NHP)-related peptides detected in the thymus from different species. We suggest that we are dealing in fact with other member(s) of the NHP hormone family, which seems to exert its activity locally through a novel model of cell-to-cell signaling, that of cryptocrine communication. This model involves exchange of signals between thymic epithelial cells and developing thymocytes. The NHP-related peptides have been shown to trigger thymocyte proliferation and could induce immune tolerance of this highly conserved neuroendocrine family.     

Study of drug control over postoperative hemorrhage after selective caesarean section

Objective: To compare the efficacy and safety of carbetocin and oxytocin in the prevention of postpartum hemorrhage after selective caesarean section. Methods: Two hundred and sixteen pregnant women who were going to deliver by caesarean section were randomly divided into two paralleled and controlled groups, of which the oxytocin group(group A) contained 105 women and the carbetocin group(group B) 111 women. 20 IU of oxytocin was administrated during operation for both groups, 10 IU directly into uterus and 10 IU intravenously. When the operation was over, 20 IU of oxytocin was dripped for group A lasting for 8 hours, while for group B 100μg of carbetocin was immediately injected intravenously for 1 minute. Blood loss as well as hemoglobin alteration was measured for the comparison of the effect of the two drugs. Blood biochemical indicators were introduced for the evaluation of the safety of carbetocin including the function of liver and kidney and the fasting glucose.Results: No significant difference was revealed between the two groups concerning the postpartum hemorrhage within 24 hours, the postpartum hemorrhage incidence and the changes of hemoglobin. There was no significant difference in the change of liver and kidney function, fasting glucose and electrolyte changes as well.Conclusions: Carbetocin has a similar effect and safety of oxytocin in controlling the blood loss of selective caesarean section.     

异丙酚无痛人工流产时静脉注射缩宫素可致血液循环严重波动

目的　观察异丙酚无痛人工流产时静脉注射缩宫素对血压和心率的影响。　方法　将 90例Ⅰ级 (美国麻醉协会麻醉术前分级 )早期宫内妊娠的患者随机分为 3组 :A组 30例 ,应用 2～ 3mg/kg异丙酚和 1μg/kg枸橼酸芬太尼进行无痛人工流产术 ,手术后期注射缩宫素 1ml,于注射后的 3min内观察收缩压、舒张压和心率变化 ;B组 30例 ,用相同麻醉方法进行无痛人工流产 ,术中不用缩宫素 ,观察指标与方法同于A组 ;C组 30例 ,不用任何麻醉药物进行人工流产 ,在与A组相同的时间注射缩宫素 ,观察指标与方法同于A组。　结果　A组在注射缩宫素后 0 5min ,血压显著下降 ,心率显著增加 ,注射后 2 .5min时 ,血压和心率基本恢复到注射前水平。B组和C组无明显血压下降。　结论　异丙酚无痛人工流产时注射常规剂量缩宫素后可致血液循环短暂严重波动 ,应引起临床妇产科医师高度重视 ,特别是对心功能储备较差的患者更应关注。     

偏头痛和慢性紧张型头痛血浆精氨酸加压素、催产素及环核着酸含量测定

用放射免疫分析法测定了２８例偏头痛、１０例慢性紧张型头痛患者和１６例健康对照组血浆精氨酸加压素（ＡＶＰ）、催产素（ＯＴ）、环磷酸腺苷（ｃＡＭＰ）及环磷酸鸟苷（ｃＧＭＰ）含量。结果表明，偏头痛发作期ＡＶＰ含量下降、ｃＡＭＰ含量升高，偏头痛间歇期ｃＧＭＰ含量下降，血浆ＯＴ含量在发作期和间歇期均明显下降。慢性紧张型头痛患者血浆ＡＶＰ、ＯＴ、ｃＡＭＰ和ｃＧＭＰ与对照组比较均无显著性差异。结果提示，血浆ＡＶＰ和ＯＴ水平降低以及环核苷酸的代谢异常与偏头痛发病机制有关。     

中缝大核内催产素在大鼠痛行为调制中的作用

目的：探讨中缝大核（NRM）内催产素（OT）在痛行为调制中的作用，及其和内源性5－HT在痛行为调制中的关系。方法：以钾离子透入法引起大鼠甩尾反应的电流强度（mA)为痛行为反应指标，测定动物痛阈，观察NRM内催产素对大鼠痛行为反应的影响。结果：NMR内注入催产素后，大鼠的痛阈明显增加；注入抗催产素血清后，大鼠的痛阈则明显降低。NRM内注入噻庚啶后，可阻断OT镇痛的效应。结论：NRM内的催产素在痛行为调制的复杂过程中发挥着一定作用，且其效应可能是通过内源性5－HT系统中介的。     

Effects of androgens and estrogens on the vasopressin and oxytocin innervation of the adult rat brain

Recently we reported that castration of rats eliminates vasopressin immunoreactivity in the lateral septum and other areas that appear to receive vasopressin innervation from the bed nucleus of the stria terminalis. Testosterone treatment counteracts this effect of castration. In the present study, we investigated whether this action of testosterone depends on its androgenic or estrogenic metabolites by treating long-term castrated rats with estradiol (E) and/or 5 alpha-dihydrotestosterone (DHT) or testosterone. The brains were then processed for immunocytochemistry or radioimmunoassay. DHT did not increase vasopressin staining in the lateral septum, although it fully restored the size of the seminal vesicles. E did restore the original fiber density, but individual fibers stained more weakly than in sham-operated males. Only treatment with both E and DHT fully restored the vasopressin innervation. This pattern was also reflected in the radioimmunoassay data. The vasopressin content of the lateral septum decreased about 90% after castration but was fully restored by either testosterone or E + DHT treatment. E alone, however, was only half as effective as E + DHT. The treatments had no effect on the oxytocin content of the septum, or on the vasopressin or oxytocin content of the dorsal vagal complex. The results suggest that E mediates most of the effects of testosterone on the vasopressin innervation of the lateral septum. DHT enhances the response to E but has little effect on its own.     

Vasopressin receptors in the mouse (Mus musculus) brain: sex-related expression in the medial preoptic area and hypothalamus

We have investigated the distribution of vasopressin binding sites in the brain of male and female adult mice using a radio-iodinated ligand and film autoradiography. Vasopressin receptors were uncovered in various regions of the brain including the basal nucleus of Meynert, the substantia innominata, the hypothalamic paraventricular nucleus, the substantia nigra pars compacta and the hypoglossal nucleus. A sex-related difference in the expression of vasopressin receptors was seen in the medial preoptic area/anterior hypothalamus corresponding to the rat sexually dimorphic nucleus in the rat and in the hypothalamic mammillary nuclei. In both structures the autoradiographic labeling is more intense in females than in males. These observations confirm that vasopressin binding sites are present in the hypothalamic preoptic area of most species examined so far and that sex-related expression of neuropeptide receptors could trigger sex-related behavioral differences.