title: [Comparative study of calixarene effect on Na+, K+ -ATPase activity in plasma membrane of contractile and mobile cells].
abstract: The paper is devoted to comparative analysis of the influence of a new class of macrocyclic compounds - calixarens on enzymatic activity of two ATP-hydrolase systems localized in the plasmatic membrane of contractile (myocytes of the uterus) and mobile (spermatozoids) cells--Na+, K+ -ATPase and basal Mg2+ -ATPase. The experiments performed on plasmatic membrane suspensions of myometrium and spermatozoids treated with detergent the authors studied the influence of calixarens C-97, C-99, C-107 (identified by the codes), functionalized with fragments of alpha-hydroxyphosphonic, alpha-aminophosphonic and methylenbisphosphonic acids accordingly, on enzymatic activity. The results have shown that C-97 and C-107 calixarenphosphonic acids in 100 microM concentration (97-99%) inhibit Na+, K+ -ATPase activity in both cases almost completely. C-99 (100 microM) calixaren appeared to be less effective with regard of its influence on the enzymatic systems under study: in the case of plasmatic membranes of myometrium suspension the activity of Na+, K+ -ATPase was decreased by 84-88%, and in the case of spermatozoids suspension--just by 15-20% of the control. All the studied calixarens (for both objects) in the maximal concentration (100 microM) practically did not influence the activity of basal Mg2+ -ATP-ase. The calixarens inhibited the enzymatic activity of Na+, K+ -ATPase more effectively than ouabain: in the first case the value of apparent inhibition constant I(0,5) was 25-100 nM, and in the second case--20-100 microM. The inhibition influence of calixarens on Na+, K+ -ATPase activity is characterized by the phenomenon of negative cooperativity (Hill's coefficient nH <1); the influence of ouabain in the case of plasmatic membranes of myometrium suspension is also characterized by negative cooperativity (nH < 1), and in case of spermatozoids suspension--by positive cooperativity (nH >1). The above results show that the studied calixarens are effective inhibitors of Na+, K+ -ATPase plasmatic membrane of contractive and mobile cells (C-97, C-99, C-107 calixarens in case of myocytes of uterus, and C-97, C-107 calixarens in case of spermatozoids).
authors.forename: T O
authors.initials: TO
authors.lastname: Veklich
authors.forename: N S
authors.initials: NS
authors.lastname: Koshechkova
authors.forename: R V
authors.initials: RV
authors.lastname: Rodik
authors.forename: V I
authors.initials: VI
authors.lastname: Boĭko
authors.forename: Z D
authors.initials: ZD
authors.lastname: Vorobets'
authors.forename: S O
authors.initials: SO
authors.lastname: Kosterin
mesh_terms: D000328:Adult; D000818:Animals; D047250:Calixarenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002462:Cell Membrane / Q000187:drug effects* / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D015394:Molecular Structure; D009119:Muscle Contraction; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000201:enzymology; D009215:Myometrium / Q000166:cytology / Q000201:enzymology; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*; D013081:Sperm Motility; D013094:Spermatozoa / Q000166:cytology / Q000201:enzymology; D013552:Swine
chemical_list: D004791:Enzyme Inhibitors; D047250:Calixarenes; D000254:Sodium-Potassium-Exchanging ATPase