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Incubation of platelet-rich plasma with 80 microM aspirin that resulted in the inhibition of both the secondary phase of ADP induced platelet aggregation and prostaglandin synthesis simultaneously stimulated the production of NO in platelets. Furthermore it was found that the treatment of platelet-rich plasma either with 80 microM ibuprofen or salicylic acid, like aspirin, which inhibited the secondary phase of platelet aggregation by ADP and prostaglandin synthesis, also stimulated the production of NO in the absence of added ADP. However the inhibition of prostaglandin synthesis by ibuprofen or salicylic acid, unlike aspirin, was transient in nature. Incubation of washed platelets with any of these three compounds also stimulated NO synthesis indicating that the effect of these compounds was not mediated through plasma proteins. The in vitro effect of aspirin on the increase of NO in platelets could also be demonstrated by in vivo exposure of platelets to the compound. It was concluded that either a temporary or a lasting inhibition of prostaglandin synthesis by these inhibitors resulted in the synthesis of NO in resting platelets. Since NO is a potent inhibitor of platelet aggregation the inhibition of platelet aggregation, by these compounds may not be the consequence of the inhibition of prostaglandin synthesis alone, but could also be related, at least partly, to the stimulated synthesis of NO by these inhibitors.

Hyperglycemia with severe reduction of plasma insulin level is frequently associated with acute ischemic heart disease. Since insulin is reported to be an anti thrombotic humoral factor, the mechanism of the impaired insulin synthesis was investigated. The plasma from the patients with acute myocardial infarction (AMI) was analyzed by SDS-polyacrylamide gel electrophoresis. Dermcidin isoform 2 (dermcidin) was determined by enzyme linked immunosorbent assay. Insulin synthesis was determined by in vitro translation of glucose induced insulin mRNA synthesis in the pancreatic β cells. Nitric oxide (NO) was determined by methemoglobin method. SDS-polyacrylamide gel electrophoresis of AMI plasma demonstrated the presence of a novel protein band of Mr 11 kDa that was determined to be dermcidin. Addition of 0.1 μM dermcidin inhibited insulin synthesis by >65 fold compared to control through the inhibition of NO synthesis in the pancreatic cells. The oral administration of 150 mg acetyl salicylic acid (aspirin) to the AMI patients increased the plasma insulin level from 13 (median) to 143 μunits/dl (median) with concomitant decrease of plasma dermcidin level from 112 to 9 nM in these patients within 12 h. It was also found that while the injection of 3.0 ± 0.05 (n = 10) nmol dermcidin with 0.25 ± 0.03 μmol ADP/g body weight caused coronary thrombus in mice, ADP itself at this concentration failed to produce thrombus. These results indicated that dermcidin was a novel platelet aggregating agent, and potentiated the ADP induced thrombosis in the animal model as well as acutely inhibited glucose induced insulin synthesis.

BACKGROUND: As a first step towards genetic improvement of seed quality in chickpea (Cicer arietinum L.), seven desi and nine kabuli varieties were grown at multiple sites to assess the affect of environment on seed yield, weight and selected seed constituents. The sites were chosen to represent a range of environments in chickpea production areas of the Canadian prairies.

A membrane bound form of nitric oxide synthase of human erythrocytes that could be activated by insulin was purified to homogeneity by detergent solubilization of the purified membrane preparation of these cells. The purified enzyme (M(r) 230 KD) was found to be composed of one heavy chain (M(r) 135 KD) and one light chain (Mr 95 KD) held together by disulphide bond(s). Scatchard plot analysis of insulin binding to the purified enzyme showed the presence of 2 different populations of the binding sites and the activation were directly related to the hormone binding to the protein. Line weaver Burk plot of the purified enzyme showed that the stimulation of the enzymic activity by insulin was related to the decrease of K(m) with simultaneous increase of V(max). Treatment of the purified enzyme with anti insulin receptor antibody inhibited the activation of the enzyme and the binding of the hormone to the protein. Furthermore NO itself, at low concentration (<0.4 microM) activated the enzyme, but at higher concentration (>0.8 microM) had no effect on the activation. Incubation of the purified enzyme with insulin simultaneously stimulated the tyrosine kinase and nitric oxide synthase activities of the preparations, that could be inhibited by genistein (an inhibitor of tyrosine kinase). These results indicated that the insulin activated nitric oxide synthase could be the insulin receptor itself.

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We study (1 + 1) dimensional Dirac equation with non Hermitian interactions, but real energies. In particular, we analyze the pseudoscalar and scalar interactions in detail, illustrating our observations with some examples. We also show that the relevant hidden symmetry of the Dirac equation with such an interaction is pseudo supersymmetry.