Influence of continued smoking and some biological risk factors on restenosis after percutaneous transluminal coronary angioplasty.

Objectives: To identify possible biological risk factors for restenosis following successful percutaneous transluminal coronary angioplasty (PTCA) in patients having single or multivessel disease. The effect of continued smoking on restenosis was also evaluated.

Design: In this prospective smoking controlled study all subjects had a routine angiographic restudy after 6 months.

Enalapril versus atenolol in the treatment of hypertensive smokers.

A randomised crossover study has been done to compare the antihypertensive efficacy of enalapril and atenolol in 45 smoking, hypertensive men. Treatment was started with enalapril 20 mg/d or atenolol 50 mg/d and, if necessary, the doses were doubled after 4 weeks to achieve a sitting diastolic blood pressure < or = 95 mm Hg, after which hydrochlorothiazide was added, if necessary. Both drugs lowered blood pressure significantly.

Exogenous GTP increases cyclic GMP and inhibits thrombin-induced aggregation of washed human platelets: comparison with ATP, adenosine and guanosine.

The effects of exogenous guanosine 5'-triphosphate (GTP), guanosine, adenosine 5'-triphosphate (ATP) and adenosine on platelet aggregation, serotonin secretion and cyclic nucleotide accumulation were studied using thrombin-stimulated washed human platelets. GTP (10 microM-1 mM) dose-dependently inhibited thrombin-induced aggregation and serotonin secretion. The inhibition of aggregation was accompanied by an increase in platelet cyclic GMP.

Endothelium-dependent and -independent effects of exogenous ATP, adenosine, GTP and guanosine on vascular tone and cyclic nucleotide accumulation of rat mesenteric artery.

1. The effects of exogenous guanosine 5'-triphosphate (GTP) and guanosine on vascular tone and cyclic nucleotide accumulation of noradrenaline-precontracted endothelium-intact and endothelium-denuded rat mesenteric artery rings were compared with the effects of the known purinoceptor agonists adenosine 5'-triphosphate (ATP) and adenosine. 2.

Modification of nitrovasodilator effects on vascular smooth muscle by exogenous GTP and guanosine.

The effects of exogenous guanosine 5'-triphosphate (GTP) and guanosine on nitroglycerin-, sodium nitrite- and SIN-1-induced guanosine 3',5'-cyclic monophosphate (cyclic GMP) accumulation and smooth muscle relaxation were studied using endothelium-denuded rat mesenteric artery rings precontracted with noradrenaline. Preincubation of contracted artery rings with GTP (100 microM) or guanosine (100 microM) before eliciting relaxations with nitrovasodilators significantly shifted the dose-response curves of nitrocompounds to the left and augmented the increases in cyclic GMP. GTP and guanosine alone also induced cyclic GMP accumulation in pre-contracted artery rings.

Effects of exercise and ethanol ingestion on platelet thromboxane release in healthy men.

We studied the effects of repeated bicycle exercises and ethanol ingestion (1.5 g/kg) on platelet aggregation and thromboxane (TxB2) release in 10 healthy male volunteers. After a bicycle exercise performed in the morning, the adenosine diphosphate (ADP)-induced platelet aggregation and the aggregation-associated thromboxane release were found to be decreased in fasting men.

Cigarette smoking alters sympathoadrenal regulation by decreasing the density of beta 2-adrenoceptors. A study of monitored smoking cessation.

We report the effects of monitored smoking cessation on adrenergic regulation in chronic smokers. The beta 2 adrenoceptor density of mononuclear leukocytes (MNLs) and plasma catecholamines was analyzed before cessation and 2, 3, and 8 weeks after cessation. We found a progressive increase in beta-adrenoceptor density after smoking cessation.

[Interaction between the arterial wall and thrombocytes in smokers].

Smoking is per se a major risk factor in cardio-vascular diseases. It causes atherosclerosis and blockage particularly in the aorta and the leg arteries. The components of tobacco smoke damage the endothelium, increase arterial contractility, and accelerate the formation of plaque therein.

Exogenous GTP enhances the effects of sodium nitrite on cyclic GMP accumulation, vascular smooth muscle relaxation and platelet aggregation.

Exogenous guanosine triphosphate (GTP) (1-2 x 10(-4)M) resulted in increased concentrations of cyclic GMP both in endothelium denuded rat mesenteric artery (RMA) and in human ADP-stimulated platelets. Sodium nitrite (3.3 x 10(-4)M) relaxed precontracted RMA by 34%.

Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath.

Eight healthy young men were studied during three periods of heat exposure in a Finnish sauna bath: at 80 degrees C dry bulb (80 D) and 100 degrees C dry bulb (100 D) temperatures until subjective discomfort, and in 80 degrees C dry heat, becoming humid (80 DH) until subjective exhaustion. Oral temperature increased 1.1 degrees C at 80 D, 1.

Decreased cyclic AMP accumulation in lymphocytes in response to adrenaline and prostacyclin after n-3 polyunsaturated fatty acid supplementation in man.

The effect of supplementation with n-3 polyunsaturated fatty acids on beta-adrenoceptor function in lymphocytes has been studied in ten healthy male volunteers. Ten Max-Epa capsules containing 320 mg n-3 polyunsaturated fatty acids per capsule were given for 3 weeks, and the cyclic AMP accumulation response in lymphocytes to adrenaline and the prostacyclin analogue iloprost (ZK 36374) were assessed before and after supplementation. After supplementation about 30% less cAMP was accumulation by the lymphocytes in response to either adrenaline or iloprost.

Decreased beta-adrenergic receptor density and catecholamine response in male cigarette smokers. A study of monozygotic twin pairs discordant for smoking.

The effect of long-term cigarette smoking on beta-adrenoceptor density and catecholamine response was studied in 10 monozygotic male twin-pairs discordant for smoking, with an average discordance time for smoking of 23 years (range, 12-35 years). The density of beta-adrenergic receptors was 40% lower in the lymphocytes of smoking twins compared with their nonsmoking cotwins (beta-receptor density, 6.7 +/- 1.

Vasoactive and atherogenic effects of cigarette smoking: a study of monozygotic twins discordant for smoking.

The mechanism by which atherosclerotic disease is induced by cigarette smoking has not yet been identified unequivocally. Chronic cigarette smoking and the generation of vasoactive prostanoids and the size of carotid atherosclerotic plaques were studied in nine pairs of identical male twins discordant for smoking for over 20 years. The urinary excretion of 2,3-dinor-thromboxane B2 (thromboxane B2 metabolite) of the smoking twin was significantly higher (on average 1.

Enhanced activation of the renin-angiotensin-aldosterone system in chronic cigarette smokers: a study of monozygotic twin pairs discordant for smoking.

Plasma renin activity (PRA) and aldosterone concentration were measured before and during submaximal exercise in 10 male monozygotic twin pairs who were discordant for smoking. In nine twin pairs PRA was higher in the smoker both at rest and during exercise. The mean PRA was 99% higher at rest and 84% higher during exercise than in nonsmokers.

Physical exercise provokes platelet desensitization in men who smoke cigarettes--involvement of sympathoadrenergic mechanisms--a study of monozygotic twin pairs discordant for smoking.

Since chronic smoking is known to be a dominant risk factor for morbidity and mortality in cardiovascular diseases related to enhanced atherogenesis and arterial thrombogenesis, the mechanisms causing these effects are of interest. The present study aims to assess the basic biochemical and haemorheological parameters among male monozygotic twinpairs, who have been discordant for smoking in average for over 20 years. Because smoking is known to cause enhanced sympathoadrenergic activation, the study was designed to further stimulate this by means of physical exercise.

Gemfibrozil decreases platelet reactivity in patients with hypercholesterolemia during physical stress.

The effects of the lipid-lowering drug gemfibrozil on platelet reactivity at rest and during submaximal exercise were investigated in 10 patients with serum cholesterol levels greater than 270 mg/dl. No significant changes were observed in platelet reactivity at rest after gemfibrozil treatment. However, a marked decrease in platelet reactivity was seen in almost all patients treated with gemfibrozil during exercise.

The increasing and decreasing effects of aromatic hydrocarbon solvents on pulmonary and hepatic cytochrome P-450 in the rat.

The effects of pretreatment with benzene and various methylbenzenes, ethyl- and propylbenzene, cumene and styrene on hepatic and pulmonary microsomal enzymes were studied in male rats. In the lungs, all the substituted benzenes, but not benzene itself, decreased cytochrome P-450 concentration, and most of them also decreased 7-ethoxycoumarin O-deethylase activity, whereas 7-ethoxyresorufin O-deethylase activity was increased by the same treatment. The change in aryl hydrocarbon hydroxylase activity was negligible.

Adrenaline infusion evokes increased thromboxane B2 production by platelets in healthy men: the effect of beta-adrenoceptor blockade.

The effects of direct adrenergic stimulation, achieved by 60-min adrenaline infusion (0.1-0.2 microgram kg-1 min-1), on thromboxane B2 (TxB2) production by platelets in whole blood ex vivo and on ADP-induced platelet aggregation were studied in seven healthy male volunteers.

Altered physiological responsiveness and decreased cyclic AMP levels in rat atria after dietary cod liver oil supplementation and its possible association with an increased membrane phospholipid n-3/n-6 fatty acid ratio.

Rats were given a cod liver oil supplemented diet and a standard diet for 4 months. The cod liver oil supplementation resulted in a marked increase in the 20:5(n-3) and 22:6(n-3) fatty acids and a marked decrease in the 20:4(n-6) fatty acid in phosphatidylcholine and ethanolamine of the atrial membrane. Atria from the cod liver oil treated rats showed a marked decrease in contractile force, heart rate and cyclic AMP (cAMP) levels under basal conditions.

The effect of pindolol on exercise-induced increase in plasma vasoactive prostanoids and catecholamines in healthy men.

The effect of intravenous pindolol (0.0256 mg/kg) on changes in plasma arachidonic acid (AA), some of its metabolites, and catecholamines induced by submaximal exercise was studied in six healthy male volunteers. Exercise resulted in markedly increased plasma concentrations of thromboxane B2 (TxB2) from 0.

Cyclic GMP affects redox state and improves energy charge of ischaemic Langendorff-perfused rat heart.

The effects of 8-bromo cyclic GMP (1 X 10(-5)M) on the levels of lactate, NAD+, NADH, AMP, ADP, ATP, creatine phosphate (CrP) and creatine were studied in the ischaemic Langendorff-perfused rat heart. The NAD+/NADH ratio and the energy charge were also calculated. The dependence of the effect of 8-bromo-cGMP on substrate availability was also studied by adding pyruvate (5 mM and 10 mM) to the perfusate, and by comparing the changes to those during perfusion with glucose alone.

The effects of cyclic AMP and cyclic GMP on redox state and energy state in hypoxic rat atria.

The effects of 8-bromo-cAMP (10(-4)M) and 8-bromo-cGMP (10(-4)M) on tissue lactate, NADH, creatine phosphate (CP), ATP, ADP and AMP were studied in hypoxic (50% oxygen saturation) spontaneously beating rat atria. CP/ATP ratio and energy charge (EC) were also calculated. In hypoxic rat atria there was a significant increase in tissue lactate, NADH, ADP and AMP and a decrease in CP, CP/ATP ratio and EC.