[The role of guanyl cyclase in the regulation of aggregation of human thrombocytes].
Increased platelet aggregability is one of the etiological factors of vascular diseases. It is suggested that the cGMP system is involved in the negative regulation of platelet aggregation. The study of platelet guanylate cyclase (GC), a key enzyme of the cGMP system, permits a more thorough understanding of biochemical control of aggregation and opens a possibility of the development of specific action on platelets in pathological states of hemostasis. The authors have revealed a high linear correlation between the increase in aggregability and the decrease in GC activity and in its response to the NO-containing compound sodium nitroprusside (SNP). During ADP-induced aggregation, the state of GC activation by SNP increases (due to saturation of the enzyme by endogenous heme); the platelet cGMP content also rises. In platelets with prevented aggregation (SNP before ADP), GC parameters remain unchanged. NP caused disaggregation of irreversibly aggregated platelets and accelerated disaggregation in the case of reversible aggregation. NO is known to be an endogenous activator of GC and this circumstance gives an opportunity of direct action on platelets (with the help of NO-containing drugs) in order to diminish their hyperaggregability and to prevent spontaneous aggregation that takes place in vascular diseases.
Chirkov
Iu Iu
IuIu
Belushkina
N N
NN
Tyshchuk
I A
IA
Severina
I S
IS
D000244:Adenosine Diphosphate / Q000037:antagonists & inhibitors / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D003470:Culture Media; D006152:Cyclic GMP / Q000097:blood* / Q000502:physiology; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D006162:Guanylate Cyclase / Q000097:blood* / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D009599:Nitroprusside / Q000494:pharmacology; D009609:Nitrous Oxide / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects / Q000502:physiology*; D010975:Platelet Aggregation Inhibitors
D003470:Culture Media; D010975:Platelet Aggregation Inhibitors; D009599:Nitroprusside; D000244:Adenosine Diphosphate; D006162:Guanylate Cyclase; D006152:Cyclic GMP; D009609:Nitrous Oxide
Rol' guanilattsiklazy v reguliatsii agregatsii trombotsitov cheloveka.