Physiologie (Bucarest) 

Abstract: Arginine vasotocin (AVT) or placebo were subcutaneously administered to 4 men at 22.00 and 01.00 h, along four nights, and polygraphic recordings were performed between 22.00 and 02.00 h during sleep. AVT significantly increased only the amount of rapid eye movement (REM) sleep (p less than 0.05), but did not influence the latency of the first REM sleep period. This effect of AVT was not dose dependent in the range between 2 and 12 microgram AVT. AVT or placebo were also intravenously injected or perfused to 10 normal adult subjects, at different times of the day, under clinical control. Doses between 2 microgram perfused 4 h and 12 microgram perfused 30 min, did not produce clinical signs of sleep. It is suggested that AVT is not a blood factor for inducing of slow waves sleep (SWS) or REM sleep in humans.

Abstract: Components of the autonomic control of the heart were studied in 5 young normals subjected to: 1) sustained lung inflation (SLI) in various postures; (2) mental loading by concentration of attention, 3) face immersion in cold water under SLI or snorkel breathing, when sitting; 4) superposition of above experimental interventions. We recorded cardiotachogram (RR interval) and T-amplitude from ECG, ear lobe photoplethysmogram, digital impedance rheogram, thermistor respiration. Cardiac data were explored by means of Fourier spectral analysis on a M 118 B microcomputer. Results caution that allegedly unilateral stimulation by some "vagal" maneuvers triggers in fact amphotropic heart rate control menus involving sympathetic nonreciprocal response. Subsequent bradycardia should be interpreted as an absolute indicator of the parasympathetic function only when a separate measure of the sympathetic counterpart is available. In vigil young adult at physical rest the medullary cardiovascular centers appear as subjected to "sliding capture" by their prominent input signal--as determined by various receptor stimulation or cortical status, the latter preserving a higher priority at competing task demands. In a coupled study 9 normals were polygraphically monitored (EEG, EOG, ear duct temperature and the above variables as well) during 2 nonconsecutive nights and cardiac data were spectrally examined along various sleep stages. Results suggest an increased dual autonomic tone during REM that could be related to reported stage-specific arrhythmias. Reciprocal dynamics of the respiratory versus lower frequency variability of RR interval from NREM to REM sleep points to a useful discriminant for computer sleep stage scoring.

Abstract: One third of 160 operatives working in a permanently noisy industrial environment, within the range of 63-8000 Hz and intensity of sound of about 100 db, were found to suffer from a syndrome of neurocirculatory asthenia and 81% from arterial hypertension Study of the ECG according to the criteria of the Minnesota code showed an increased frequency of upward deflection of ST segment (index 9-2) in 206% of the cases, depression of the ST segment with an ascending orientation in 5062% of the cases and left ventricular hypertrophy (index 3-1 and 3-3) in 20% of the cases Audiometry revealed loss of hearing at frequencies of 4000 CS in 161% of the cases The results obtained suggest that the detrimental effects are not restricted only to hearing, but also that the alterations detected might evolve towards organic cardiac disorders

Abstract: Chronic and acute effects of L-Carnitina (vials of 1 g L-Carnitina endovenous; per orally administered vials of 1 g L-Carnitina; tablets of 1 g L-Carnitina) were recorded in 110 top athletes (rowing, kayak-canoe, swimming, weightlifting medium and long-distance runners), 47 girls and 63 boys, by six double blind placebo trials and cross over. Significant changes were registered after L-Carnitina treatment (both for a single dose or after 3 weeks of treatment) compared to placebo, for FFA, triglycenides, lactic acid after exercise, evoked muscular potential, plasma carnitine (free and acetyl-carnitine), urine carnitine (free carnitine) and others. The authors explain these changes by the increase of free carnitine, which permits a larger quantity of FFA to enter the mitochondria and to be more extensively used as energy source in endurance and strength efforts. Based on these results the authors recommend L-Carnitina as an ergogenic aid in elite athletes, especially in endurance and strength sports.