THE EFFECT OF ENDOGENOUS OESTROGEN ON PLASMA AND URINARY CALCIUM AND PHOSPHATE IN OOPHORECTOMIZED WOMEN

Using a specific radioimmunoassay, significant levels of plasma oestradiol can be detected in the blood of oophorectomized women. In these women the plasma concentration of oestradiol correlates positively with the body fat content. Low circulating concentrations of oestradiol are associated with increased values for serum phosphate and alkaline phosphatase, but no significant change in serum calcium. The fasting urinary calcium creatinine ratio is inversely related to circulating plasma oestradiol concentration which also correlates, in a more complex way, with the renal threshold for phosphate (TmPO₄/GFR). It is suggested that oestrogen production may be an important factor in determining bone loss in post-menopausal women.     

醋酸钙与碳酸钙改善血透患者钙磷代谢的对比研究

目的：为了寻找一种安全有效的降磷药物。方法;在３７名维持性血液透析患者中试用醋酸钙代替碳酸钙治疗,并自身对照。结果;醋酸钙可以更有效地降低血磷,虽然出现了血钙的升高,但是钙磷乘积却显著性地降低。结论;醋酸钙是一种新型的,有效的降磷升钙药物,对改善维持性透析患者的钙磷代谢,防止肾性骨病的发生有着积极的作用。     

EFFECTS OF EXOGENOUS CATECHOLAMINES AND EXERCISE ON PLASMA MAGNESIUM CONCENTRATIONS

Catecholamines and physical exercise are known to influence the metabolism of several minerals in man, but the effects on magnesium (Mg) have been scarcely investigated. In the present study, infusion of adrenaline (5 micrograms/min for 30 min followed by 10 micrograms/min for 30 minutes) significantly reduced the plasma Mg levels in healthy males. This effect was abolished by simultaneous infusion of propranolol. Noradrenaline had no such effect. In order to stimulate endogenous catecholamine release healthy males carried out physical exercise in four different ways: ergometer bicycling at maximum load until exhaustion with and without oral beta-blockade, ergometer bicycling with stepwise increasing load until exhaustion, isokinetic maximal exercise with one leg, with blood sampling both from the venous effluent of the exercising leg and the opposite resting arm and long-term (60 min) steady state ergometer bicycling at approximately 65% of estimated maximum capacity. During short-term (less than 20 min) intense exercise (i.e. experiments 1-3) the plasma Mg concentrations were increased. This was probably due to a reduction of plasma volume and to an influx of Mg to the vascular pool. During long-term steady state exercise (experiment 4) the Mg levels were not significantly affected but decreased during the first hour of recovery. These results suggest that both the beta-adrenergic system and muscular activity by itself affect Mg homeostasis.     

THE EFFECTS OF CHRONIC SMOKING ON THE FIBRINOLYTIC POTENTIAL OF PLASMA AND PLATELETS

We studied tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) in healthy individuals divided by smoking habit into current smokers, former smokers and non-smokers (who had never smoked). Plasma PAI-1 antigen was significantly higher in smokers than in non-smokers with intermediate levels in former smokers. A similar trend was observed for plasma PAI activity but this did not reach statistical significance. Platelet PAI-1 and plasma t-PA were not significantly different when comparing the three groups. After venous occlusion t-PA rose significantly in all groups; no significant change in plasma PAI-1 was observed. The ratio of t-PA to PAI-1 in plasma was similar in non-smokers and former smokers but lower in smokers, suggesting that there is at least partial restoration of plasma fibrinolytic potential after smoking cessation. Plasma PAI-1 antigen and PAI activity correlated with estimated pack-years of cigarettes smoked among smokers and former smokers. When all subjects were studied collectively, plasma PAI-1 correlated strongly with plasma t-PA and triglycerides; plasma t-PA also correlated strongly with triglycerdes.
We conclude that chronic smoking is associated with impaired fibrinolysis in plasma and that this largely reflects elevated plasma PAI-1 in smokers. Smoking does not appear to affect the response to venous occlusion. The postulated effect of chronic smoking on plasma PAI-1 may be mediated by the influence of smoking on triglycerides and insulin resistance. Stopping smoking appears to return impaired fibrinolysis towards normal. Smoking does not quantitatively affect the platelet pool of PAI-1. Smoking habit should be controlled for in clinical analyses of PAI-1 and t-PA.     

Graves病治疗前及治疗中血清游离钙与血,尿钙磷代谢异常

46例Graves病患者治疗前血清游离钙(Ca~( ))、磷(P)、碱性磷酸酶(AKP)及24小时尿钙(Ca)、P、羟脯氨酸(Hyp)排量水平都显著高于正常对照组。经治疗2—3个月甲亢病情控制后,血Ca~( )、P及24小时尿Ca、P亦随之恢复正常,但血AKP与24小时尿Hyp仍高于对照组。高钙血症比率在血Ca、校正钙与Ca~( )测定中分别为11.2％、16.3％与30.0％。前臂骨密度呈现骨量减少和腰椎相示骨质疏松者分别为29.0％和13.3％。本文对Graves病患者的钙、磷和骨代谢改变及其发生作了初步讨论。     

心血管应激和芬太尼对血浆心钠素水平的影响

本实验探讨全麻气管插管心血管应激及芬太尼作用对血浆心纳素水平的影响。结果显示，实验组气管插管心血管应激反应明显，血浆心钠素水平伴随升高，且与血压心率的增加呈高度正相关关系。而对照组在给予６μ８·ｋｇ（－１）芬太尼抑制气管插管应激反应时，插管期间循环兴奋性明显减弱，血浆心钠素水平亦未见升高。因此说明：①血浆心钠素水平与气管插管心血管应激程度密切相关，是气管插管应激指标之一；②芬太尼不参与人类血浆心钠素水平的调节。     

从血浆促肾上腺皮质素释放素样生物活性和神经递质类药物的作用探讨Cushing病病因

用大鼠垂体细胞灌流技术和ACTH直接法放射免疫测定研究了正常人、Cushing病患者和其他下丘脑-垂体-肾上腺轴疾病患者血浆中的促肾上腺皮质素释放素样生物活性,结合Cushing病患者对神经递质类药物的反应所作观察提出如下假设:绝大多数Cushing病原发于垂体,在发病过程中,高皮质醇血症损害海马,削弱其对下丘脑-垂体-肾上腺轴的抑制作用是一个重要环节。     

FAMILIAL HYPOCALCIURIC HYPERCALCAEMIA I: RENAL HANDLING OF CALCIUM, MAGNESIUM AND PHOSPHATE

Ten hypercalcaemic members from three generations of a family with familial hypocalciuric hypercalcaemia (FHH) were compared with age and sex matched healthy subjects. Two of the former had undergone unsuccessful subtotal parathyroidectomy. Our results showed that the hypercalcaemia was mainly attributable to an increased capacity for tubular reabsorption of calcium, but in part also to an increased release of calcium from bone. The relative hypermagnesaemia had a similar dual origin. The serum phosphate concentration was low and this could be accounted for in full by a decrease in renal tubular reabsorption of phosphate, as assessed by the renal threshold phosphate concentration (TmPO4/GFR). The results of PHT measurements with two radioimmunoassays were equivocal. Most patients had normal serum PTH values, but with one assay mean serum PTH was significantly higher in the hypercalcaemic group. We conclude that the abnormalities of the divalent cation and phosphate metabolism cannot be accounted for in full by increased circulating PTH activity, and are predominantly due to an intrinsic renal abnormality.     

EFFECTS OF HIGH-DOSE AND LOW-DOSE NALOXONE ON PLASMA ACTH IN PATIENTS WITH ACTH HYPERSECRETION

The effect of a high (5.4 mg/h) and a low (0.8 mg/h) dose of naloxone (i.v. over a period of 90 min) on ACTH secretion was compared with placebo in patients with Addison's disease, congenital adrenal hyperplasia, Cushing's disease or Nelson's syndrome. In seven patients with primary adrenal insufficiency the high dose of naloxone provoked a significant increase of plasma ACTH concentrations (P less than 0.02) whereas the low dose of naloxone failed to influence ACTH secretion. In six patients with ACTH dependent Cushing's disease or Nelson's syndrome both doses failed to alter plasma ACTH levels. These results support the concept of inhibitory delta- or kappa-opiate receptors in the regulation of ACTH secretion. In patients with Cushing's disease or Nelson's syndrome ACTH secretion is insensitive to naloxone, presumably because of an autonomous pituitary adenoma or hypothalamic derangement.     

钙拮抗剂对3T6成纤维细胞的影响

采用流式细胞技术（ＦＣＭ）观察不同剂量的四种钙拮抗剂（Ｃａ－Ａ）汉防已甲素（Ｔｅｔ）、硝苯啶（Ｎｉｆ）、维拉帕咪（Ｖｅｒ）及脑益嗪（Ｃｉｎ）对３Ｔ６成纤维细胞生长增殖的影响，结果表明它们不仅可阻断Ｇ１→Ｓ期的进程，而且抑制Ｓ期ＤＮＡ的含量，但却增加Ｇ１和Ｇ２期蛋白质的含量，使细胞呈现不平衡生长，最终死亡。其中Ｔｅｔ的作用最为显著，呈一定的量效关系，此作用与阻断钙离子内流无关。提示钙拮抗剂对３Ｔ６成纤维细胞生长增殖的抑制可能是其抗肝纤维化的机制之一。     

依那普利对充血性心力衰竭患者血浆儿茶酚胺和血淋巴细胞β受体的影响

本文测定54例充血性心力衰竭(CHF)患者血浆儿茶酚胺[CA:包括去甲肾上腺素(NA)、肾上腺素(A)、多巴胺(DA)]和血淋巴细胞β受体密度(L-BAR),并以15例正常人作为对照。结果表明,CHF患者血浆CA显著增高,其中NA增高更为突出,可反映心功能的受损程度;L-BAR仅重症者显著降低;NA、A与L-BAR呈显著负相关。依那普利(Enalapril)治疗后,NA显著降低,A、DA和L-BAR无明显变化,心功能改善。     

THE EFFECTS OF HALOTHANE ON PLASMA VASOPRESSIN DURING CARDIO-PULMONARY BYPASS

Plasma vasopressin concentrations were estimated in twelve patients undergoing cardio-pulmonary bypass for open heart surgery. In six patients anaesthesia was maintained with 66% nitrous oxide in oxygen, whilst the remaining six additionally received halothan as a vasodilator during the bypass period. Induction of anaesthesia had little effect on plasma vasopressin concentrations, whilst marked increases were seen during surgery and bypass in both groups of patients. However, in those patients receiving halothane, significantly higher concentrations were reached, a maximun b36.1 +/- 8.9 (SEM) muu/ml being seen in contrase to 15.4 +/- 2.2 muu/ml in the group receiving nitrous oxide in oxygen alone.     

EFFECTS OF CYTOKINES ON ALKALINE PHOSPHATASE AND OSTEOCALCIN PRODUCTION, CALCIFICATION AND CALCIUM RELEASE BY HUMAN OSTEOBLASTIC CELLS

We examined the effect of TNF-     

EFFECTS OF CHANGE IN BODY POSTURE ON PLASMA AND SERUM ELECTROLYTES IN NORMAL SUBJECTS AND IN PRIMARY ALDOSTERONISM

We observed that change in body posture from the supine to the erect position in normal volunteers was associated with a rise in circulating potassium and a fall in sodium concentrations, irrespective of whether the electrolytes were measured in serum or plasma, or whether head-up tilt or ambulation was used. In patients with primary aldosteronism, the fall in serum sodium and rise in serum potassium with ambulation tended to obscure the characteristic electrolyte abnormalities of that syndrome. These changes in potassium and sodium could contribute to the rise in aldosterone secretion on orthostasis. The body posture of patients should be considered in the interpretation of plasma and serum electrolyte levels.     

Graves病患者一次静脉注射葡萄糖酸钙及EDTA后血浆PTH、钙、磷的动态变化

作者观察了正常人及Graves病患者静脉注射葡萄糖酸钙、EDTA后血浆PTH、钙、磷的变化。静注葡萄糖酸钙、EDTA后,正常人组血清钙迅速上升或下降,血浆PTH亦随之下降或升高;Graves病组血钙亦迅速上升或下降,而血PTH无明显动态变化。血钙与PTH无明显相关性。提示Graves病患者在血钙的平衡调节中,PTH以外的因素起主要作用,并认为甲状旁腺功能有缺陷。     

钙剂加维生素D治疗对糖尿病患者钙代谢的影响

本文报道NIDDM患者在常规治疗的基础上加用钙剂和维生素D治疗后的钙代谢变化。糖尿病患者单纯用常规治疗控制血糖后,负钙平衡不能完全纠正,而加用钙剂和维生素D治疗后,负钙平衡能完全纠正,并且高于正常对照组平衡值(P<0.01)。说明钙剂加维生素D治疗对糖尿病性骨质疏松是有益的。