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Adenylate kinase (AK, EC 2.7.4.3) is a ubiquitous phosphotransferase which catalyzes the reversible transfer of high-energy β - and γ-phosphate groups between nucleotides. All classified AKs show a similar structure: they contain a large central CORE region, nucleoside monophosphate and triphosphate binding domains (NMPbd and NTPbd) and the LID domain. Analysis of amino acid sequence similarity revealed the presence of as many as nine human AK isoenzymes, which demonstrate different organ-tissue and intercellular localization. Among these kinases, only two, AK1 and AK2, fulfill the structural and functional criterion by the highest affinity for adenine nucleotides and the utilization of only AMP or dAMP as phosphate acceptors. Human AK isoenzymes are involved in nucleotide homeostasis and monitor disturbances of cell energy charge. Participating in large regulatory protein complexes, AK supplies high energy substrates for controlling the functions of channels and transporters as well as ligands for extracellular P2 nucleotide receptors. In pathological conditions AK can take over the function of other kinases, such as creatine kinase in oxygen-depleted myocardium. Directed mutagenesis and genetic studies of diseases (such as aleukocytosis, hemolytic anemia, primary ciliary dyskinesia (PCD)) link the presence and activity of AK with etiology of these disturbances. Moreover, AK participates in regulation of differentiation and maturation of cells as well as in apoptosis and oncogenesis. Involvement of AK in a wide range of processes and the correlation between AK and etiology of diseases support the medical potential for the use of adenylate kinases in the diagnosis and treatment of certain diseases. This paper summarizes the current knowledge on the structure, properties and functions of human adenylate kinase.

The aim of the study was to estimate the usefulness of rest 99mTc-MIBI SPECT scintigraphy to evaluate carbon monoxide cardiotoxicity in acute group poisonings. There were 7 study patients (5 men and 2 women) aged from 14 to 35 years treated at the Department of Clinical Toxicology intoxicated with CO at three different sites: three persons were intoxicated at one, two persons at the second and the next two persons at another site of exposure. As derived from interview the circumstances, source and duration of exposure were similar within the separate group. This enables a comparison of clinical course of carbon monoxide poisoning, particularly the circulatory system of people who were simultaneously exposed to the same source of carbon monoxide. Measurement of COHb, blood lactate level, duration of exposure and ECG examination were performed on admission to the Clinic. The enzymes activity (ALT, AST, CPK) were evaluated after 24 hours. The rest 99mTc-MIBI SPECT scintigraphy was performed in all patients two to five days after intoxication. The changes in myocardial scans were graded according to the arbitrarily accepted point scale. Considering the results of ECG and enzymes activity only, no objective were found to diagnose the cardiac dysfunction. However the perfusion scintigraphy scans indicated regions of myocardium that have decreased blood flow in all the study patients.

Objective: To estimate the influence of electrical cardioversion on the left ventricular systolic function, left atrial size, the plasma activity of creatinine phosphokinase (CPK) and its myocardial fraction (CK-MB) and plasma level of atrial natriuretic peptide (ANP) in patients with paroxysmal atrial fibrillation caused by coronary artery disease, hypertension or mitral valve disease., Patients: The study underwent 36 patients with paroxysmal atrial fibrillation of mean duration 24.5 hours in which sinus rhythm was restored by electrical cardioversion., Methods: Plasma activity of creatinine phosphokinase (CPK) and its myocardial fraction (CK-MB), plasma level of atrial natriuretic peptide (ANP) and echocardiographic examination were obtained before and 24 hour after electrical cardioversion. During echocardiographic examination were measured left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), left atrial size (LA) and early diastolic velocity(E) and velocity with atrial contraction (A) of left ventricular inflow. Electrical cardioversion was initiated with impulse of 100 J. If it failed to convert atrial fibrillation to sinus rhythm next impulse of 200 J and 360 J were consequently applied., Results: In all subgroups of patients formed dependently on a number of electrical shocks, 24 hour after cardioversion significant increase in left ventricular ejection fraction (LVEF) and decrease in plasma level of ANP were noted. In subgroup of patients treated with 1 (100 J) and 2 (100 + 200 J) impulse significant decrease in left atrial size was found out. The increase in plasma activity of creatinine phosphokinase (CPK) and its myocardial fraction (CK-MB) was confined to the subgroup treated with 3 (100 + 200 + 360 J) impulses. No changes in left ventricular end diastolic diameter (LVEDD) and early velocity (E) of left ventricular inflow 24 hours after cardioversion were observed. In all patients electrical cardioversion brought about the appearance of atrial wave of left ventricular inflow. No differences in estimated parameters between patients with coronary artery disease, hypertension and mitral valve disease were observed. Significant positive correlation between plasma level of ANP and left atrial size before (r = 0.69, p < 0.001) and after cardioversion (r = 0.68, p < 0.0001) were found., Conclusions: Restoration of the sinus rhythm in patients with paroxysmal atrial fibrillation leads to the increase in left ventricular ejection fraction (LVEF) and to the decrease in left atrial size (LA) and the plasma level of atrial natriuretic peptide. Left atrial size and plasma level of ANP are related. The cardioversion with impulses of high energy increases the plasma activity of creatinine phosphokinase and its myocardial fraction.

An activity of some selected indicator enzymes in rats after adrenalectomy, stimulation and inhibition of adrenal glands has been investigated in the heart muscle. An increase in the activity of CPK, isoenzyme CK-MB, LDH and AspAT after the adrenal stimulation (Synacthen) have been observed. As well as significant decrease in the activity of these enzymes after adrenalectomy and inhibition (by use Orimeten-aminoglutethimide) functioning of adrenal glands have been observed.

Pathomorphological changes of the cardiac muscle of experimental rabbits and rats intoxicated with Intration were traced. Diffuse ischaemic lesions such as the presence of large quantities of mitochondria, contraction nodes and droplet necrosis were observed. These lesions result: from the toxic effect of pesticides on myocytes and inhibition of cholinesterases as well as from nonphysiologically great activity of lysosome enzymex which are also responsible for necrotic lesions in the cardiac muscle. Excessively high PAM doses administered to animals intoxicated with pesticide result in lesions in the cardiac muscle of rabbits and rats which are greater than after administering an insectide alone. Toxobidin, a multi-function compound, doses not possess such negative properties as PAM.

In the blood of rabbits and rats poisoned with Intration, after 1, 3, 6 and 10 days of the experiment activities of AChE and ChE as well as those of beta-GR, AcP, AP and KT were checked. In addition, in the cardiac muscle, kidneys and liver, marker lysosomal hydrolases, i.e. beta-GR and AcP were determined. A long-standing reduction in the activities of AChE and ChE and increase in the activities in the concentrations of nonphysiologically great lysosomal hydrolases and AP were noted. A correlation between the inhibition of cholinesterase and organic lesions was found. Lysosomal enzymes share the responsibility for the necrotic process or rabbits' and rats' cardiac muscles. The use of oximes (PAM and Toxobidine) considerably contributed to reactivation of AChE and ChE and to normalization of the test marker enzymes.

It has been found that ATP-ase activity increases considerably in the heart after intravenous administration of adrenaline, noradrenaline, phenylephrine (50 micrograms/kg), phentolamine, atropine, and also after vagotomy and adrenaline given after vagotomy. In the skeletal muscle ATP-ase activity increases considerably after noradrenaline, isoprenaline, phenylephrine (50 micrograms/kg), adrenaline given after phentolanine and Ach given after denervation of the muscle. A decrease in the activity of the enzyme in the heart was found after propranolol hexamethonium and Ach given after vagotomy, whereas in the skeletal muscle after Ach, hexamethonium and after muscle denervation. No changes or weak actions in the skeleton muscle are evoked by phenylephrine (10 micrograms/kg), propranolol, atropine, tubokurarine as well as adrenaline given after muscle denervation. In the heart, however, isoprenaline, Ach, adrenaline after propranolol, Ach after atropine and Ach after hexamethonium. A very low involvement of the enzyme studied in utilization of ATP reserves in the heart and skeletal muscle was found. However, of significant importance in this process may be the reactions catalized by extramembrane ATP-ases. The autonomic nervous system effects ATP-ase activity, and stimulation of beta-adrenergic receptor causes an increase in the enzyme activity in both muscles, whereas stimulation of the muskarine receptor decreases the enzyme activity in the heart. Moreover, it was found that stimulation of N2 receptor of the motor plate results in increased ATP-ase activity in the skeletal muscle. The present studies have not brought enough evidence accounting for participation of alpha-adrenergic receptor in regulation of the enzyme studied.

The object of the study was rats myocardium. Tissue samples were examined 3, 6 and 12 hours after carbon tetrachloride treatment. The poison was administered by a gastric tube in single dose of 0.6 ml/100 g body weight. The examination carried out by the histochemical method revealed changes in the intensity of enzymatic reaction, whereas due to the Selye staining fuosynophylic fibres were found.