Immunomodulatory activity of met-enkephalin and its two potent analogs.

The effects of Met-enkephalin (Met-Enk), a delta receptor binding opioid peptide, and its more stable synthetic analogs, Tyr-D-Ala-Gly-MePhe-Met-NHC3H7-iso (1), Tyr-D-Ala-Gly-MePhe-Gly-NHC3H7-iso (2) and Tyr-D-Ala-Gly-MePhe-Gly-NHCH2C6H5 (3), on human T-cell transformation and natural killer (NK) cell cytotoxicity have been evaluated. Analogs 1 and 2 have been found to be as potent as Met-Enk in stimulating T-cell transformation and augmenting NK cell cytotoxicity. Analog 3 had no effect on T-cell transformation and NK cell cytotoxicity.

Effect of fertilizer diammonium phosphate on liver, kidney and muscle 5'-nucleotidase activity of fresh water teleost fish Clarias batrachus.

The toxic effect of fertilizer Diammonium phosphate resulted in alterations of 5'-Nucleotidase activity of tissues--liver, kidney and muscles of fish C. batrachus at varying intervals and exposures. Alterations in 5'-Nucleotidase activity of body organs gave an idea of the toxicity caused by the fertilizer.

von Willebrand factor and endothelial damage in essential hypertension.

The relationship between von Willebrand factor antigen (vWFAg, a specific endothelial cell product) and hypertension was examined. Circulating vWFAg levels were measured in serum from patients attending a hypertension clinic and in normotensive controls. The vWFAg was higher in those patients with uncontrolled hypertension at 131 +/- 34 IU/dl than in controls (90 +/- 30 IU/dl) and in those whose hypertension was controlled 104 +/- 29 IU/dl (P < 0.