Effect of Unsymmetrical Dimethylhydrazine on Isolated Heart and Lymphatic Vessels.

Unsymmetrical dimethylhydrazine (UDMH, heptyl) and its derivatives are used in the rocket and space industry as components of rocket fuel. UDMH is a highly toxic compound exhibiting irritant, hepatotoxic, and neurotoxic properties. In this study, the toxic effect of heptyl on isolated rat heart and lymphatic vessels was demonstrated. Acute exposure to UDMH leads to vasoconstriction of the coronary vessels of the isolated heart and pronounced stimulation of isolated lymphangions starting from the concentration of 10-4 M. The changes are dose-dependent. After exposure to UDMH in high concentrations (10-2 M), the changes in the functional parameters became irreversible. The obtained results provide evidence for the organ-specific effect of UDMH on visceral muscle organs.

Effect of Endomorphin-1 on Contractile Activity of Rat Mesenteric Lymphatic Vessels.

We studied the effect of endomorphin-1 on isolated mesenteric lymphatic vessels in rats. It was found that endomorphin-1 caused a dose-dependent increase in the contractile activity of lymphangions, which was associated with stimulation of intracellular calcium depots. The observed effect of endomorphin-1 in isolated lymphatic vessels has a complex mechanism; it depends on the concentration of the applied peptide and is probably determined by its interaction with non-opioid receptors.