Hypertension is emerging as an important public health problem in sub-Saharan Africa. We studied blood pressure (BP) patterns, hypertension and other cardiovascular risk factors in a rural and an urban area of The Gambia. A total of 5389 adults (у15 years) were selected by cluster sampling in the capital Banjul and a rural area around Farafenni. A questionnaire was completed, BP, pulse rate, height and weight were recorded. Glucose was measured 2 h after a 75 g glucose load among participants у35 years (n ‫؍‬ 2301); total cholesterol, triglycerides, creatinine and uric acid were measured among a stratified subsample (n ‫؍‬ 1075). A total of 7.1% of the study participants had a BP у160/95 mm Hg; 18.4% of them had a BP у140/90 mm Hg. BP was significantly higher in the urban area. BP increased with age in both sexes in both areas. Increasing age was the major independent risk factor for hypertension. Related cardiovascular risk factors (obesity, diabetes and

The position of both the body and the arm during indirect blood pressure (BP) measurement is often neglected. The aim of the present study was to test the influence of the position of the patient on BP readings: (1) sitting with the arms supported precisely at the right atrium level and (2) supine: (a) with the arms precisely at the right atrium level and (b) with the arms on the examination bed. In a first group of 57 hypertensive patients, two sessions of BP and heart rate (HR) measurements were performed in two positions: sitting and supine with the arms supported precisely at right atrium level in both positions. BP was measured simultaneously at both arms, with a Hawksley Random Zero sphygmomanometer at the right arm, and with an automated oscillometric device (Bosomat) at the left arm. BP and HR readings obtained in the two positions were then compared. In a second group of 25 normoand hypertensive persons, two sessions of BP and HR readings were performed in supine with the arms in two different arm positions: (a) the arm placed precisely at right atrium level and (b) the other arm on the examination bed. The measurements were performed at both arms with two automated devices (Bosomat). The readings taken in the two positions were compared. Both systolic BP (SBP; by 9.5 7 9.0 (standard deviation, s.d.); right arm) and diastolic BP (DBP; by 4.8 7 6.0 mmHg; right arm) were significantly higher in the supine than in the sitting position. When the two different arm positions (body continously supine) were compared in the second part of the study, significantly higher SBP (by 4.6 7 6.1 mmHg) and DBP (by 3.9 7 2.8 mmHg) were obtained when the arm of the patient was placed on the bed (below the right atrium level), than when the arm was placed at the level of the right atrium. BP readings in sitting and supine positions are not the same. When according to guidelines the arm of the patient is meticulously placed at the right atrium level in both positions, the difference is even greater than when the arm rests on the desk or on the arm support of the chair. Moreover, in the supine position small but significant differences in BP are measured between arm on a 5 cm-high pillow and arm on the bed. In every study reporting BP values, the position of both the body and especially the arm should be precisely mentioned.

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In 1983, Noma [1] was the first to describe that an outward potassium current increased significantly when guinea pig or rabbit cardiac muscle cells were subjected to hypoxia. This current was caused by the activation of potassium channels, which was independent of the intracellular Ca 2+ concentration, but dependent on the intracellular concentration of adenosine-5 ′-triphosphate ([ATP] i ). These so-called ATPsensitive potassium (K ATP ) channels were suggested to play a cardioprotective role during ischaemia. Later, K ATP channels were also found in skeletal muscle [2], smooth muscle [3] and pancreatic beta cells [4] from animals. In pancreatic beta cells the K ATP channels mediate insulin secretion [5] and are a target for sulphonylurea derivatives in the treatment of non-insulin-dependent diabetes mellitus (NIDDM) [6]. Sulphonylurea derivatives are highly specific in blocking pancreatic and cardiovascular K ATP channels, and Diabetologia (1996Diabetologia ( ) 39: 1562Diabetologia ( -1568 Blockade of vascular ATP-sensitive potassium channels reduces the vasodilator response to ischaemia in humans Summary Experimental data show that ATP-sensitive potassium (K ATP ) channels not only occur in pancreatic beta cells, but also in the cardiovascular system, where they mediate important cardioprotective mechanisms. Sulphonylurea derivatives can block the cardiovascular K ATP channels and may therefore interfere with these cardioprotective mechanisms. Therefore, it is of clinical importance to investigate whether sulphonylurea derivatives interact with vascular K ATP channels in humans. Using venous-occlusion strain-gauge plethysmography, we investigated whether ischaemia-induced reactive hyperaemia is reduced by the sulphonylurea derivative glibenclamide in 12 healthy male non-smoking volunteers. Forearm vasodilator responses to three periods of arterial occlusion (2, 5 and 13 min) during concomitant infusion of placebo into the brachial artery were compared with responses during concomitant intra-arterial infusion of glibenclamide (0.33A control study (n = 6) showed that time itself did not change the vasodilator response to ischaemia.Glibenclamide significantly increased minimal vascular resistance (from 2.1 ± 0.1 to 2.3 ± 0.2 arbitrary units, Student's t-test: p = 0.01), and reduced mean forearm blood flow (from 37.5 ± 2.0 to 35.4 ± 2.0 ml ⋅ min -1 ⋅ dl -1 after 13 min occlusion, ANOVA with repeated measures: p = 0.006) and flow debt repayment during the first reperfusion minute (ANOVA with repeated measures: p = 0.04). In contrast, total flow debt repayment was not affected. Infusion of glibenclamide into the brachial artery resulted in local concentrations in the clinically relevant range, whereas the systemic concentration remained too low to elicit hypoglycaemic effects. Our results suggest that therapeutic concentrations of glibenclamide induce a slight but significant reduction in the early and peak vasodilation during reactive hyperaemia.

1. It is known that females have a lower skin perfusion than males. In women there are also differences in blood flow at different reproductive stages of their lives. As an initial investigation of the possible contribution of sex hormones to these differences, we studied skin and forearm blood flow during the natural changes in hormone levels which occur during the menstrual cycle. 2. Thirty-one healthy female volunteers were studied. The effect of a standardized finger cooling test (immersion of a gloved hand in a 16 degrees C water bath) on finger skin temperature and on laser Doppler flux in the finger, and forearm blood flow (strain gauge venous occlusion plethysmography) was assessed at four different times during one cycle: during menstruation, 1 day before ovulation, 2 days after ovulation and at the mid-luteal phase. Test days were determined by daily measurements of basal body temperature and were confirmed afterwards by determinations of serum luteinizing hormone, follicle-stimulating hormone, 17 beta-oestradiol and progesterone. 3. Peripheral skin circulation varied significantly within one menstrual cycle. The extremes were a mean finger skin temperature of 25.9 +/- 3.0 degrees C in the luteal phase compared with 28.4 +/- 3.7 degrees C in the pre-ovulatory phase (P = 0.002). The respective values for the mean laser Doppler flux were 18.4 +/- 10.9 compared with 29.2 +/- 16.4 arbitrary units (P = 0.003). 4. Baseline forearm muscle blood flow also varied significantly (P = 0.04) within one menstrual cycle, with low values in the menstrual phase compared with the other phases.(ABSTRACT TRUNCATED AT 250 WORDS)