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Biomedical subjects

G R Venning

Publications and source records attributed to G R Venning.

28 records · Page 2Linked to original sources
PubMed1981

Bioassay of a new aldosterone antagonist and evaluation of a simple method of quantitative comparison.

The renal antimineralocorticoid activity of single oral doses of a new aldosterone antagonist OH OPC(ME)-K was compared to that of spironolactone in two studies in healthy men. OH OPC(ME)-K reversed the urinary electrolyte response to fludrocortisone in the period up to 16 hr after treatment, but it was less potent than spironolactone on a weight basis. The best estimate of the relative potency of OH OPC(ME)-K: spironolactone (derived from a simple protocol using equal single doses of the two drugs) was 0.60:1 (95% confidence limits 0.24:1 to 1.42:1), in good agreement with the estimate from a more complex three-dose parallel-line bioassay (0.61:1, 95% confidence limits 0.48:1 to 0.79:1). The results of simple single-dose studies can be used, with certain assumptions, to provide a useful estimate of the relative potency of new aldosterone antagonists at an early stage of development.

Double-Blind Method↗
PubMed1980

Activity of sulfur-containing intermediate metabolites of spironolactone.

The renal antimineralocorticoid activity of single administration of 2 sulfur-containing compounds, which are thought to be intermediate metabolites of spironolactone, was assessed in healthy subjects. They were each active in reversing the urinary electrolyte changes indiced by fludrocortisone for 2 to 10 hr after dosing, but only the 7 alpha-thiomethyl derivative exhibited activity in the period 12 to 16 hr after treatment. The activity of both drugs was less than of spironolactone. Taking urinary log 10 Na/K as the best index of antimineralocorticoid activity, the potencies of the intermediates relative to spironolactone were 0.26 (95% confidence limits, 0.12 to 0.49) for 7 alpha-thio-spirolactone and 0.33 (95% confidence limits, 0.15 to 0.62) for 7 alpha-thiomethyl-spirolactone in the period 2 to 10 hr after medication. We conclude that these minor sulfur-containing intermediate metabolites of spironolactone are unlikely to contribute significantly to the renal antimineralocorticoid activity of spironolactone.

Adult↗
PubMed1977

Ethical review in the pharmaceutical industry.

1. There seems no reason why clinical pharmacology studies conducted within the pharmaceutical industry should be exempt from the requirement of ethical review, and independent review in this situation reduces the vulnerability of the company and its employees, in addition to serving its primary function of protecting the volunteer subjects. 2. Experience within one company has shown that independent ethical review need not seriously influence the pace of research. 3. It is important that such committees should be seen to be independent and competent.

Drug Evaluation↗
PubMed1976

The rhythm of the normal human heart.

The 24-hour cardiac rhythm was studied in 86 subjects (41 male, 45 female) aged 16-65 years, after exclusion of 15 additional volunteers with suspected abnormalities. The electrocardiogram was recorded continuously for two 24-hour periods. In this apparently normal population, 10 subjects (12%) had disturbances of rhythm which are widely believed to be of serious prognostic significance; they included frequent ventricular ectopic beats, R-on-T and multifocal ventricular ectopic beats, bigeminy, and ventricular tachycardia. Supraventricular tachycardia, infrequent ventricular ectopic beats, junctional rhythm, and second-degree heart block were also observed, and if these are included most of the subjects showed some disturbance of rhythm. Bradyarrhythmias and tachyarrhythmias were equally common in waking hours and during sleep. These disturbances were not confined to the older age-groups. Heart-rate but not the number of arrhythmias was significantly higher in smokers.

Adolescent↗