Low-dose captopril in chronic heart failure: acute haemodynamic effects and long-term treatment

The acute haemodynamic effects of low doses of the oral converting-enzyme inhibitor, captopril, were studied in 18 patients with severe chronic heart failure. The effects of long-term therapy were also evaluated. Increasing doses (1 mg, 2.5 mg, 6.25 mg, 12.5 mg, and 25 mg) of captopril were given at 2 h intervals with haemodynamic monitoring. Graded haemodynamic improvement (increased stroke-volume index and reduced mean pulmonary capillary wedge pressure) was noted from 1 hand was closely associated with reduction of blood pressure. Maximal haemodynamic improvement for the group was seen at 6 h and 7 h after the 6.25 mg and 12.5 mg doses, when stroke-volume index had risen 35% and mean pulmonary capillary wedge pressure had fallen 40% from control. Captopril 12.5-50 mg every 8 h was continued long term but was withdrawn in 2 patients with symptomatic hypotension and 1 patient with altered taste. 4 patients died and 1 was noncompliant with therapy. At 3 months, 10 patients showed significant improvement in symptoms, treadmill-exercise duration, and echocardiographic indices of left-ventricular size and function. Repeat haemodynamic measurements were similar to optimum measurements obtained during the initial study.

Antenatal plasma exchange therapy

A 22-year-old primigravida with severe mesangiocapillary gomerulonephritis presented at 10 weeks gestation for antenatal care. Delivery of a small health infant was achieved by caesarean section at term. The successful outcome of this pregnancy was attributed to the careful control of anaemia, oedema, and hypertension; and to the use of plasma-exchange therapy throughout the third trimester. The value of plasma exchange therapy in pregnancies which are complicated by renal disease is discussed.

[Study of folic acid blood levels during estro-progestagen treatments]

When the blood levels of folates were estimated in 100 women following treatment with oestro-progestagens the following facts emerged : 1) There is no significant difference between the folate levels found in women on oestro-progestagens compared with a control population of the same age. 2) We have not found any evidence of frank folic acid deficiency in women on oestro-progestagens, but there have been slight drops in the levels of folates in women who show other reasons for folic acid deficiency than taking oral contraceptives. These are : troubles in absorption, salmonella, an increase in the need for folic acid in pregnancy, and failure of transport. Furthermore the incidence of lower levels in the control population was exactly the same as in the experimental population.

Direct association of messenger RNA labeled in the presence of fluoroorotate with membranes of the endoplasmic reticulum in rat liver

Liver rough endoplasmic reticulum (RER) membranes were isolated from rats given [3H]orotic acid for 48 h (ribosomal RNA [rRNA] label) or for 3 h along with 5-fluoroorotate; this latter procedure permits the labeling of cytoplasmic messenger RNAs (mRNAs) in the absence of rRNA labeling. More than 50% of the labeled mRNA remained attached to membranes of the RER after complete removal of ribosomes with a buffer of high ionic strength in the presence of puromycin. Under similar conditions, membranes retained 40% of their polyadenylate as determined by a [3H]-polyuridylate hybridization assay. Treatment of mRNA-labeled endoplasmic reticulum membranes with pancreatic RNase indicates that the polyadenylate and possibly nonpolyadenylate-pyrimidine portions of the messenger are involved in the binding of mRNA to the membranes. The implication of these results in furthering our understanding of the mechanisms of the translational regulation of genetic expression is discussed.