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The myocardial ATP concentration is significantly decreased in failing hearts, which may be related to the progressive loss of the myocardial total adenine nucleotide pool. The total myocardial interstitial purine metabolites (IPM) in the dialysate of interstitial fluid could reflect the tissue ATP depletion. In rats, postmyocardial infarction (MI) left ventricular (LV) remodeling was induced by ligation of the coronary artery. Cardiac microdialysis was employed to assess changes of IPM in response to graded beta-adrenergic stimulation with isoproterenol (Iso) in myocardium of hearts with post-MI LV remodeling (MI group) or hearts with sham operation (sham group). The dialysate samples were analyzed for adenosine, inosine, hypoxanthine, xanthine, and uric acid. LV volume was greater in the MI group (2.2 +/- 0.2 ml/kg) compared with the sham group (1.3 +/- 0.2 ml/kg, P < 0.05). Infarct size was 28 +/- 4%. The baseline dialysate level of uric acid was higher in the MI group (18.9 +/- 3.4 micromol) compared with the sham group (4.6 +/- 0.7 micromol, P < 0.01). During and after Iso infusion, the dialysate levels of adenosine, xanthine, and uric acid were all significantly higher in the MI group. Thus the level of IPM is increased in hearts with postinfarction LV remodeling both at baseline and during Iso infusion. These results suggest that the decreased myocardial ATP level in hearts with post-MI LV remodeling may be caused by the chronic depletion of the total adenine nucleotide pool.

At present time in the SRC--Institute of Biophysics the data bank containing the information on the reactions of 431 dogs to radiation exposure in a wide range of doses has been created. By the results of 4299 blood tests reporting a leukocyte content, including 2509 tests reporting a blood formula, the individual peculiarity of the peripheral blood reaction in dogs were analyzed. Dose dependencies for the reaction of blood-forming system to radiation exposure to doses in the range from 1.0 to 7.0 Gy were obtained. In comparison with the similar data for humans, the neutrophil content in peripheral blood decreased approximately 1.5-2.0 times faster in dogs than in men, resulting in earlier recovery.

Antiradiation therapeutic efficiency of translam (1-->3; 1-->6-beta-D-glucan) produced by enzymatic synthesis out of laminarin, polysaccharide of Laminaria cychorioides, has been studied in four animal species (mice, guinea-pigs, dogs, monkeys). A stable curative effect has been observed following its administration within first 24 h after radiation exposure at doses that cause acute radiation sickness (about LD90). The preparation is nontoxic and has a broad therapeutic range which permits its practical application.

We present the results of a long-standing experimental development of ways and means for acute radiation sickness treatment that have been authorized for application in medicine and are mostly aimed at large-scale accidental injuries. The paper describes means for early treatment (prodigiosan, desoxynate, typhoid vaccine, proteus vaccine), a myeolopoiesis stimulant (estradiol dipropionate), a detoxication procedure (hemosorption), substitution therapy with bone marrow cells and peripheral blood mononuclears, anti-infectious schemes comprising antibiotics and polyvitamins.

Changes in mean blood pressure (MBP), heart rate (HR), diuresis, natriuresis and kaliuresis, which had been evoked by intravenous bolus administration of the synthetic atrial natriuretic peptides (ANP) ANP (99-126), ANP (103-126), ANP (103-125), and ANP (103-123) in doses of 10 and 60 micrograms/kg each, were studied during 2% body weight volume expansion by intraarterial injections of 0.9% NaCl in awake rats. All the ANP analogues were indicated to decrease MBP and induce differential changes in HR. All the ANP analogues, except ANP (103-123), increased diuresis and natriuresis in the first 30 min of the experiment.

The effects of endothelin (0.1 nMol/kg and 1 nMol/kg into the left ventricle) on hemodynamics and cardiac contractility were investigated in conscious and unrestrained, WKY rats before and during continuous infusion of atriopeptides (1 microgram/kg/min i.v.). Bolus injection on endothelin into the left ventricle caused a transient hypotension and tachycardia followed by a long-lasting increase in mean blood pressure (MBP) and bradycardia in intact rats. In the rats receiving constant atriopeptide infusions, the hypotensive phase of endothelin effects was augmented whereas the hypertensive phase was reduced. Endothelin doses dependently increased cardiac contractility parameters during the first 3 minutes after injection. The stimulation of cardiac function at this time resulted from reflex responses due to the rapid decrease in the MBP. These effects were followed by decreases in cardiac contractility indices. Infusion of atriopeptide led to a tendency to the positive inotropic action of and augmented the negative inotropic action of endothelin.

The effects of endothelin (0.1 and 1 nmol/kg into the left ventricle) on mean blood pressure (MAP), heart rate (HR), central venous pressure (CVP), and mean circulatory filling pressure (MCFP) were investigated in conscious and unrestrained WKY rats before and during continuous infusion of atriopeptide (1 mu mk/kg/min i.v.). In intact rats, bolus injection of endothelin into the left ventricle caused a transient hypotension followed by a long-term increase in MAP. In the rats receiving atriopeptide infusion constantly, the hypotensive phase of endothelin effects was augmented whereas the hypertensive phase was reduced. Low doses of endothelin did not affect CVP and MCFP while the highest dose given to intact rats and atriopeptide-treated rats caused small, but significant decreases in CVP and MCFP. Our results suggest that endothelin has small effects on total body's venous tone in contrast to its effectiveness by increasing blood pressure.

The systemic and regional hemodynamic effects of endothelin: a new vasoconstrictor peptide, were studied in alert WKY rats. The radioactive microsphere technique was used to measure cardiac output, total peripheral resistance and regional blood flow before and 10 min after bolus injection of endothelin into the left ventricle. Endothelin produced a transient hypotension followed by a long-lasting increase in blood pressure and in systemic resistance and a decrease in cardiac output. Endothelin induced a decrease in blood flow in all vascular beds to variable extent (the maximal changes were recorded in kidneys and adrenals), only the coronary blood flow being increased. In the rats receiving constant atriopeptine II infusion, the hypotensive phase of endothelin effects was augmented whereas the hypertensive phase was reduced. Atriopeptine II infusion also diminished the regional blood flow responses to endothelin in the kidneys, the adrenals and the heart.

Changes in the arterial pressure (AP), heart rate (HR) and sensitivity of chronotropic baroreceptor reflex (SBR) evoked by i. v. infusion of alpha-ANP, AP-III, AP-II, and AP-I (1 mg/kg/min) were studied in alert Wistar rats. The SBR was tested by infusion of phenylephrine or sodium nitroprusside. All the ANP analogues, except AP-1, were shown to decrease the AP and evoke differential changes in the SBR. The SBR evoked by phenylephrine was increased by 60-80%, whereas SBR evoked by sodium nitroprusside was decreased by 30-60%. The specific changes in tachycardic and bradycardic components of the baroreceptor reflex after ANP analogues infusions seem to reflect participation of the baroreceptor reflex in the mechanism of ANP-induced hypotension.

The authors studied tissue lipids of flesh and liver of squids, the most important industrial objects in the Far East basin. Among them there were Todarodes pacificus, Ommastrephes bartrami, Berrytenthis magester, Sepia officinalis. Total lipids in flesh fluctuated from 0.50 to 2.61%. The liver of all squid species contains from 15.00 to 54.6% of lipids. The sum of lipids in the cuttlefish liver is from 5.43 to 12.30%. Lipids in edible tissues contain high amounts (50-55%) of phospholipids and monoglycerides. The following saturated fatty acids (SFA) prevail: C16:0 (from 14.68 to 28.64%). C14:0 (from 0.24 to 2.23%), C12:0 (from 0.25 to 2.82%). The cuttlefish lipids are characterized by the highest level of monounsaturated fatty acids: C16:1 (10.51%). C22:1 (13.59%). The content of polyunsaturated fatty acids in lipids of Bartram and Comandor squids and cuttlefish comprises 47.59-49.84%. C20:5 (5.40-20.20%) promotes a normal functioning of the cardiovascular system. The level of SFA in the Bartram squid liver lipids is more than 2 times lower (33.28/14.17) than in the tissue lipids, while in the Pacific Ocean (17.59/13.23), Comandor (39.20/30.71) squids and cuttlefish (20.39/17.82) they are at about the same level. The lipids of Comandor squid liver contain 22.98% of C16:0. The levels of the following acids are especially high: C18:1 (5.66-25.18%), C16:1 (1.49-20.32%), C22:1 (2.49-8.69%), C22:5 (4.13-6.83%), C20:5 (6.16-10.68%), C22:6 (3.10-10.18%), C20:4 (2.4-22.06%).