Effects of cobalt sulfate on prenatal development of mice, rats, and rabbits, and on early postnatal development of rats.

The effects of cobalt sulfate administered to pregnant C57BI mice, OFA-SD rats, and New Zealand rabbits was studied on fetal and postnatal offspring. Cobalt concentration in the maternal blood was increased in proportion to the administered doses. Cobalt crossed the placenta and appeared in the fetal blood and amniotic fluid. Regardless of the administered dose of cobalt sulfate, cobalt concentration in the blood peaked 2 h after administration. Cobalt produced dose-dependent maternal toxicity and was found to be embryotoxic in all three species, as evidenced by elevated frequency of fetuses with body weight or skeletal retardation and embryolethality. Cobalt increased the frequency of major anomalies significantly in mice and rats, with anomalies of the eyes, kidneys, skull, spine, and sternum in mice, and anomalies of the urogenital system in rats. Cobalt sulfate was not teratogenic in rabbits. Intra-amnial administration of cobalt sulfate produced a dose-dependent increase of the frequency of dead fetuses, and weight retardation of the live fetuses. The direct cytotoxic effect probably plays a role in the embryotoxic and teratogenic effects of cobalt. The postnatal examinations revealed a decrease of the perinatal index in the treated group. The body weight of the pups in the treated group was lower during wk 1 of life, but no difference was found between the control and treated by the end of wk 2. Eye opening was completed in the usual time period in both groups, while time of appearance of the teeth, descending of the testes, shaping of ears, and development of hearing was delayed in the treated group. The development of muscle strength and of the locomotor system was delayed. All the functions studied (forward movement, swimming, righting reflex) normalized by postnatal d 21, with the exception of muscle strength. It was concluded that cobalt sulfate exposure decreases the perinatal viability of the fetuses, but the functions of the surviving fetuses with perinatal retardation become compensated by postnatal wk 2-3. The development of fetuses is undisturbed thereafter.

Hemodynamic effect of indium chloride in pregnant rats.

Daily indium chloride doses of control (0) or 200 mg/kg were administered orally to pregnant Sprague-Dawley (SD) rats by gavage, on d 6-15 of gestation. On d 16 of gestation hemodynamic tests were performed; Arterial blood pressure, cardiac output (CO), and volume organ blood flow were determined with radioactive microspheres using the reference sample method (McDevitt & Nies, 1976). Indium chloride increased the cardiac index (CI), but did not change arterial blood pressure and total peripheral resistance (TPR). Indium decreased the organ fractions of the cardiac output to kidneys, ovaries, uterus, and placenta, while those to brain, lungs, and liver were not affected. In the placenta the blood flow was reduced significantly while the vascular resistance increased. The blood flow and vascular resistance did not change in the rest of the organs studied. The changes in arterial blood pressure, CO, Cl, TPR, organ fraction of cardiac output, blood flow, and vascular resistance in most of the organs displayed normal responsiveness to noradrenaline (NA) infusion. The reduction of uterine and placenta fractions and placental blood flow, produced by NA infusion were significantly greater in control than in the indium-treated group. Data indicate that the hemodynamic changes induced by indium are detrimental to the fetus. Indium chloride exposure modifies the maternal effect of noradrenaline such that there is maternal survival at the expense of fetal mortality.

Embryotoxic and teratogenic effects of indium chloride in rats and rabbits.

Daily indium chloride doses of control (0), 50, 100, 200, or 400 mg/kg were administered orally to Sprague-Dawley rats by gavage, on d 6-15 of gestation, and daily metal doses of control (0), 50, 100, or 200 mg/kg were administered to New Zealand rabbits on d 6-20 of gestation. Further groups of pregnant rats were treated with control (0) or 400 mg/kg indium chloride orally on one of d 8, 9, 10, 11, 12, 13, 14, or 15 of gestation. The dams and fetuses were examined on d 21 (rats) and 30 (rabbits) of gestation, using standard teratological methods. Indium concentration was determined in the maternal and fetal blood, as well as in the amniotic fluid, by atomic absorption spectrometry. Indium was found to cross the placenta and appeared in fetal blood in proportion to the metal concentration of the maternal blood. In the amniotic fluid, indium concentrations remained below the detection limit. In rats, indium chloride produced dose-dependent maternal toxic effects, with a dose of 400 mg/kg inducing embryotoxicity (embryolethality) and teratogenicity. Doses of 200 and 100 mg/kg were embryotoxic (retarding) and teratogenic, causing skeletal and visceral anomalies in addition to external anomalies (rudimentary or missing tail, syndactylia, clubfoot, exencephalia) in rats. In rabbits, 200 mg/kg indium chloride was lethal for the dams and the embryos (some of the animals died, and the number of abortions and full resorptions increased). This dose was found to be teratogenic (caused gross renal anomalies) and increased the frequency of fetuses with skeletal retardation. In rats, the effects of indium chloride causing fetal retardation was found to be independent of exposure time. The teratogenic effects were the highest on d 11 and 12 of gestation, when indium chloride caused gross external malformations. Data suggest that the teratogenic effects of indium chloride can be attributed primarily to a direct cytotoxic action of indium resulting from placental transfer, but the effect is not a selective one, as it appears only in the presence of maternal toxic effects.

Haemodynamic effect of nickel chloride in pregnant rats.

Non-pregnant and pregnant CFY rats were given 3 mg/kg nickel chloride or physiological saline by gavage daily for eight days during days 7-14 of organogenesis. The haemodynamic investigations were carried out using 113Sn labelled microspheres. Nickel concentrations in maternal and fetal blood, as well as in amniotic fluid were determined by atomic absorption spectrophotometry. It was found, that nickel crossed the placenta, appeared in the fetal blood and amniotic fluid, where its concentration depended on the dose given to the pregnant animal and the nickel concentration of the maternal blood. Nickel chloride influenced neither the systemic haemodynamic parameters (arterial blood pressure, total peripheral resistance--TPR, cardiac index) nor the values of the organ (including the placenta) circulation indices, neither in the pregnant nor in the non-pregnant animals. It is concluded that in the pathomechanism of embryotoxicity (causing weight gain retardation) and teratogenicity (causing major anomalies of the uropoietic apparatus) of nickel, demonstrated earlier, the assumed effects of nickel on maternal and placental circulation probably do not play role (as such effects could not be detected). The direct embryo-damaging effect of nickel crossing the placenta (direct cytotoxic effect) may be held responsible for the embryotoxicity and teratogenicity of nickel.

The combined cardiovascular effect of alcohol and noise in rats.

Groups of 20 CFY male rats were made to drink water containing 10% alcohol and 5% sugar or 5% sugar. Half of both groups (10-10 animals) were exposed to 95 dBAeq mixed industrial noise for 3 weeks, 6 hours daily. Haemodynamic measurements were carried out using isotope (57Co) labelled microspheres, which were repeated after the i.v. administration of 30 micrograms/kg/3 min noradrenaline, using a second isotope (113Sn). It was found, that alcohol decreased the cardiac fraction of the cardiac output, the nutritive blood flow of the myocardium and increased the vascular resistance of the adrenals. Noise decreased the lung fraction of the cardiac output and the hepatic blood flow. Interaction between noise and alcohol, inhibiting the effect of alcohol, was demonstrated on the intestinal blood flow, adrenal fraction of cardiac output and testicular vascular resistance. The haemodynamic effects of noradrenaline observed in the control were in several organs more or less modified in the animals treated with alcohol or noise or both. It was concluded that the exposures (alcohol, noise or both) modify the alpha-adrenergic effect of noradrenaline.

The effects of simultaneous alcohol and nickel sulphate poisoning on the cardiovascular system of rats.

Two groups of male OFA rats received 10% ethanol and 5% sugar, or 5% sugar in their drinking-water. One half of each group received 5 mg/kg b.w. daily dose of nickel sulphate in 10 ml of physiological saline by gavage, for three weeks, while the other half of the groups received 10 ml physiological saline. Morphological (light and electron microscopic) and haemodynamic (radioactive microsphere method) examinations were performed. It was found, that alcohol caused decreases of borderline significance of the arterial blood pressure and the nutritive blood flow of the heart, while nickel sulphate significantly increased the arterial blood pressure, the vascular resistance of the kidneys, liver and brain, increased TPR in a tendinous way. Following a simultaneous administration of alcohol and nickel considerably increased the arterial blood pressure (statistically interaction at a level of borderline significance) and caused the appearance of swollen mitochondria and dilated sarcoplasmatic reticulum in the ultrastructure of the heart. It is concluded, that 1. pathomechanism of myocardium-damaging effects of nickel sulphate and alcohol is different; 2. nickel sulphate and alcohol together (at least in a certain dose range) increase the arterial blood pressure.

The effects of simultaneous alcohol and cobalt chloride administration on the cardiovascular system of rats.

CFY male rats received drinking water which contained 10% ethyl alcohol and 5% sugar and were treated with 50 mg/kg daily doses of cobalt chloride for three weeks by gavage. Haemodynamic examinations were carried out using radioactive microspheres. Alcohol caused no significant injury of the structure of the myocardium, while cobalt chloride caused incipient multifocal myocytolysis. Blood pressure and nutritive blood flow of the heart were decreased slightly by alcohol and significantly by cobalt chloride. Alcohol additively increased the effect of cobalt chloride decreasing the nutritive blood flow of the heart. It is suggested, that hypoxia increased by dual exposure is responsible for the aggravating effect of alcohol on the myocardial injury caused by the cobalt salt.

Hypertension and alcoholism.

Blood pressures of 122 patients, undergoing alcohol withdrawal treatment in hospital, were taken at admission and one and two weeks after admission, and various laboratory tests that are thought to be the markers of alcoholism (gamma glutamyltransferase--GGT, mean corpuscular volume--MCV, serum uric acid) were performed (by the authors). At admission 27% of the patients had hypertension. The GGT and MCV exceeded the upper level of the normal range in 75% and 68% respectively of the group studied. 70% of the high MCV values was between 96-100 fl, it was closed to normal value. Out of 122 alcoholics 8 patients had serum uric acid levels higher than the upper limit (420 mumol/l), and in 14% of the alcoholics this level was found near the upper limit (350-420 mumol/l). Among the laboratory markers of alcoholism and the alcohol-associated parameters there was a relationship only between the GGT and daily alcohol consumption, so 13% of the change in GGT value was explained by the daily dose of alcohol consumption. There was a significant interaction between GGT and systolic blood pressure, as well as between serum uric acid and systolic blood pressure. These laboratory markers give explanation for the blood pressure change in 16% of the cases. From the two laboratory markers only the effect of GGT proved to be significant: above 200 GGT value the probability of high systolic blood pressure increases. It was also found, that alcohol withdrawal after two weeks decreased blood pressure in the majority of alcoholics, and after two weeks the average of systolic and diastolic blood pressure was significantly lower than at admission.

Identification of health damage due to alcohol abuse; importance of alterations in cardiac function and blood chemistries.

Like in any other disease, diagnosis of health damage caused by alcohol abuse can be established all the easier and sooner, the more results of medical examinations are taken into consideration simultaneously. Evidence is presented that a larger proportion (96.4%) of alcoholics suffer from compromised cardiac function (the classification function uses 6 variables out of the measured 21 than from disorders of liver function and the metabolism (87.7%) (the classification function uses 12 variables out of the 21). Taking into consideration all the 41 variables (using only 12) the power of discrimination is 99.2% (discriminant analysis).

Acute effects of low doses of alcohol on the cardiovascular system in young men.

.15, 0.25 and 0.5 g/kg alcohol in the form of 40% brandy in one week intervals was consumed by eight healthy, regularly trained young men volunteers. Blood alcohol level, blood pressure and ECG were registered before and 30, 60 and 90 min after, each alcohol consumption. The cardiac output was measured with a radiocirculographic method before and 45 min after alcohol consumption. The cardiac index, stroke volume, stroke index, and total peripherial resistance (TPR) were calculated. With increase of the alcohol dose the blood alcohol level increased, while cardiac output, cardiac index, stroke volume, stroke index, and the systolic blood pressure fell. The other parameters examined--heart rate, diastolic blood pressure, TPR among others--remained unchanged. The ECG was normal. The highest no effect alcohol dose was less than 0.15 g/kg (approximately 0.1 g/kg). It is concluded that, depending on the dose, alcohol has practically no effect on the majority of the heart-functions, however, in the range of 0.1 to 0.5 g/kg it has a depressive influence, i.e. lowers the pump-function of the heart and, at 0.5 g/kg the arterial blood pressure. Evaluation of the quantitative and qualitative relationships of dose-effect and dose-response of the human heart following acute alcohol consumption needs experiments with various doses in homogeneous groups as well as toxicological investigations in animals.

Morphological alterations due to long term alcohol intake in rats.

The myocardium and blood vessels of 20 rats kept for one year on DeCarli and Lieber's liquid diet containing alcohol to 36% of total Joules were examined with routine histological, histochemical and electron microscopical methods. No changes in the gross anatomy, histology, histochemistry and electron microscopy of the arteries, veins and capillaries were found. Subcellular damage of the atrial and ventricular myocardial cells was observed. A varying number of mitochondria were affected in each of the animals: degenerated mitochondria, mitochondria with electron lucent matrix, with concentric cristae, of bell shape, with negative succinic dehydrogenase activity or vacuolated mitochondria were found. In 10% the myofibrils, and in 30% the sarcoplasmic reticulum were damaged. Secretion and lipofuscin granules increased in number in 25% of the animals. It is concluded that although the submicroscopic alcoholic alterations are similar to some of those reported in experimental ischaemia, the decrease in myocardial blood flow may not be held solely responsible for the alcoholic damages. A toxic effect of alcohol, acetaldehyde and catecholamine is postulated.

Experimental models for studying the effects of ethanol on the myocardium.

The ability to induce alcoholic cardiomyopathy has been tested in a variety of animal species. Myocardial alterations consistent with subclinical heart disease have been produced in many of these studies through a direct effect of ethanol or its metabolites upon the heart or a neurohumoral mechanism. In the rat most studies have, however, failed to finding diminished contractility in the basal state. In long-term animals the acute left ventricular responses to isoproterenol and calcium as well as pacing were reduced. Long-term studies in mongrel dogs fed 36 per cent of calories as ethanol produced an early decrease in left ventricular diastolic compliance related to interstitial collagen accumulation. Diminished contractility developed by four years. In addition to the morphologic evidence of distorted sarcoplasmic reticulum, in vitro experiments suggest important acute effects. Each mole of ethanol is bound tightly to each mole of protein comprising the Ca-ATPase pump, which is inhibited. Impaired uptake and binding of calcium by the sarcoplasmic reticulum has been observed in chronic alcohol models at one to two day intervals following the last exposure to ethanol. In addition, the flux of calcium ion does not appear normal in terms of access to contractile protein, where the calcium regulated inhibition of the troponin interaction with myosin is impaired. Experimental studies in a canine model of alcoholism revealed that the ventricular fibrillation threshold was moderately reduced in the basal state after 18 months and was diminished further after acute exposure.

Effects of quantitative undernourishment, ethanol and xylene on coronary microvessels of rats.

The effect of alimentary deficiency, ethanol intake and exposure to xylene on the coronary microvessels and heart weight were investigated in rats. The coronary microvessels of rats, which were undernourished for 5 weeks and which were fed ad libitum were studied with the histomorphometric method of Herrmann et al [19]. In another experiment a group of rats was fed a control liquid diet while another group was fed a liquid diet containing ethanol up to 36% of the total Joule intake. One-half of both groups were placed in an exposure chamber supplied with pure air; the other two half-groups were made to inhale air containing 1000 mg xylene/m3 for 6 h daily, 5 days a week, for a period of 4 weeks. It was found that undernourishment did not cause any morphological reactions in the microvessels and did not affect the relative heart weight. Ethanol increased the contractile activity of the wall cells of coronary microvessels, and also the relative heart weight. The effect of xylene was similar to that of the ethanol. The effect of xylene in combination with ethanol was additive on the one hand (in some parameters), on the other hand there was an inhibition between the effects of the two chemicals (in the case of the number of mv. 10.5 micron less than d less than 21 micron). It is concluded that both ethanol and xylene increase the vascular tone of coronary microvessels and this alteration causes a decrease in the nutritive myocardial blood flow. Undernourishment does not play any role in the increase of vascular tone.

Long-term effects of ethanol on coronary microvessels of rats.

To study the hitherto unknown long-term effects of ethanol on the contractile activity of wall cells of coronary microvessels (mv.), 21 experimental and 21 control animals were investigated, using a new histomorphometric method. The pair-fed rats of the experimental group were given a diet containing ethanol which replaced 36% of the total calories for 4 weeks. This resulted in an increase of wall thickness of mv. in all segments of the microvasculature and an augmentation of the number of ATP-hydrolyzing small-calibered mv. The increase of wall thickness of muscularized mv. was interpreted as a structural adaptation to a long-term predominance of vasotonic influences, which were apparently likewise responsible for the increase of ATP-hydrolysis in the smallest mv. The possible reasons for this predominance are discussed and the necessity to include myocardial metabolic factors in pathogenic considerations on ethanol-induced coronary affections is indicated. Such mv. reactions as observed may be considered as a potential contributive pathogenic factor in ethanol-induced cardiomyopathies and hypertension.

Chemical-induced changes in hepatic vascular innervation.

The aim of this work was to reveal the chemical-induced consequences of reversible and irreversible liver injury on the neural elements of liver vessels and to study the means of adaptation of the neuro-vascular unit to the compensatory changes during functional demands in the process from damage to regeneration. The effects of selective and non-specific hepatotoxic agents were studied in rats in acute and long-term poisoning. Acute intoxication with chemicals causing no obvious tissue destruction resulted in a decrease in the number of detectable monoaminergic nerve terminals and dense core vesicles of axons, and an increase in number of mast cells, in acute poisoning upon the effect of chemicals axondegeneration was not found. Long-term alcohol intoxication brought about hyperinnervation in the liver, decrease in blood pressure and hepatic arterial blood flow. The decrease in hepatic arterial blood flow due to noradrenaline was significantly less than in the control. During different stages of long-term carbon tetrachloride poisoning the alterations of hepatic innervation in the central and peripheral area of macroscopic liver lobe were not uniform. It is concluded that the experimentally altered environment transforms the target organ, which, in turn, can be regulated only by an adequately altered control unit. However, the functional-morphological unit operating compensatorily by means of a new innervation may respond to extraneuronal transmitters with a reaction different from that of the normal tissue.

Changes in cardiac function in the "preclinical" stage of alcoholic heart disease.

In 103 out of 220 alcoholics (46.8%) with no heart disease electrocardiographic abnormalities were found, sinus tachycardia, T-wave irregularities and intraventricular conduction disturbances being the most common features. Comparing 138 chronic alcoholics with those of 134 healthy abstainers for the systolic time-intervals, the following abnormalities were found in the former group: prolonged PEP and ICT, shortened LVET, increased PEP/LVET and heart rate. Correction of the time intervals for heart-rate left the direction of the changes unaffected. Nor was the age of the subjects found to affect the intervals to any significant degree either in the alcoholics or in the control group. It is therefore assumed that the effect of alcohol on the time-intervals operates through at least two mechanisms, an increase in heart-rate, and a depression of myocardial contractility.

Effect of long-term alcohol intake on the cardiovascular system of the rat.

A group of rats was fed on control liquid diet, while another group was fed on liquid diet containing alcohol up to 36% of the total calories. After 4, 8 and 12 weeks of treatment ECG, haematocrit, histological structure of the heart, blood pressure, cardiac output, distribution of the organ fraction of cardiac output (by Sapirstein's method and 85Sr labelled microsphere technique), nutritive blood flow and circulatory resistance of the organs were studied. A mild repolarization disturbance was shown by the ECG record of the alcohol exposed animals. Haematocrit values and the histological structure of the heart did not change in any of the groups. Relative heart weight increased, blood pressure, total peripheral resistance and nutritive blood flow of the myocardium decreased, while myocardial vascular resistance increased. There was no significant interaction between the effects of alcohol and the duration of exposure to alcohol for any of the parameters monitored. It is concluded that chronic alcohol intake should be taken into consideration in aetiology of ischaemic heart disease.

Effect of chronic exposure to alcohol on the circulation of rats of different ages.

Two groups each of young and old animals were fed nutritonally adequate liquid diet. One group of each served for control, while in the other one 36% of the total caloric intake was supplied by ethanol in place of part of the fat and carbohydrate. The young animals became rapidly adapted to the alcohol containing diet, while the aged animals refused to eat it even at the expense of transient hunger and thirst. Alcohol treatment resulted in body weight loss and the appearance of slight ST segment abnormalities in the ECG. Histological study of the myocardium revealed no pathological finding. Alcohol reduced the blood pressure, TPR, gut and skin fractions of the cardiac output, myocardial nutritive blood flow, and vascular resistance of the carcass in both groups, whereas it increased the relative weight of the heart. There was a greater decrease of blood pressure and a greater increase in the relative weight of the heart in the old than in young alcohol treated animals. Chronic exposure to alcohol results in a redistribution of circulation which is detrimental to cardiac function. This alcohol induced redistribution affects the cardiovascular system of old animals more severely.