RESUMEN
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.
Asunto(s)
Dimetilhidrazinas , Vasos Linfáticos , Animales , Dimetilhidrazinas/toxicidad , RatasRESUMEN
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.
Asunto(s)
Calcio/metabolismo , Vasos Linfáticos/efectos de los fármacos , Vasos Linfáticos/metabolismo , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Oligopéptidos/farmacología , Receptores Opioides mu/metabolismo , Animales , Masculino , RatasRESUMEN
We have studied the effect of Ð -endorphin (an endogenous opioid peptide) on the functional characteristics of isolated rat heart. In physiological concentrations (6.3 X 10-10 M) Ð -endorphin induces a negative inotropic effect, accompanied by a slight decrease in the heart rate, and has no effect on the perfusion pressure of the coronary vessels. It is shown that the effect of Ð -endorphin is mediated by 5-opioid receptors. ATP-dependent K+-channels contribute the greatest contribution to the implementation of the effect of Ð -endorphin on the isolated heart of a rat. The role of voltage-dependent K+-channels and NO-mediated mechanisms in the implementation of the effects of Ð -endorphin is minor.
Asunto(s)
Frecuencia Cardíaca/efectos de los fármacos , Corazón/fisiopatología , Contracción Miocárdica/efectos de los fármacos , betaendorfina/farmacología , Animales , Masculino , Técnicas de Cultivo de Órganos , Canales de Potasio/metabolismo , Ratas , Receptores Opioides delta/metabolismoAsunto(s)
Endotelio Vascular/fisiología , Histamina/farmacología , Ganglios Linfáticos , Vasos Linfáticos , Mesenterio/anatomía & histología , Contracción Muscular , Animales , Difenhidramina/farmacología , Relación Dosis-Respuesta a Droga , Endotelio , Agonistas de los Receptores Histamínicos/farmacología , Antagonistas de los Receptores Histamínicos H1/farmacología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/fisiología , Vasos Linfáticos/anatomía & histología , Vasos Linfáticos/efectos de los fármacos , Vasos Linfáticos/fisiología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , RatasRESUMEN
The role of regulatory peptides is the least explored part in the field of humoral regulation of lymphatics. In this paper we continue a systematic investigation of their effects on the lymphatic vessels of various animals. The effect of thyroliberin was studied on bovine mesenteric lymphatics. The isolated lymphatics contractility and smooth muscle cell electrical activity were investigated. Thyroliberin in ultra low concentrations (1 x 10(-13)-1 x 10(-18) M) exerts a considerable stimulating effect. The mechanism of the theroliberin ultra-low concentrations action and a possibility of the medical usage of the obtained results, are discussed.
Asunto(s)
Sistema Linfático/fisiología , Músculo Liso/fisiología , Hormona Liberadora de Tirotropina/fisiología , Animales , Bovinos , Electrofisiología , Técnicas In Vitro , Sistema Linfático/efectos de los fármacos , Masculino , Mesenterio , Contracción Muscular , Músculo Liso/efectos de los fármacos , Hormona Liberadora de Tirotropina/farmacologíaRESUMEN
Glucocorticoids were found to affect the membranes of lymphatic vessels' myocytes. Mechanisms of this action were studied.