RESUMEN
The essential oil of the leaves of Eugenia sulcata, in the Myrtaceae family, has a demonstrated antihypertensive effect, but its effects on heart muscle and its toxicity have not yet been elucidated. Little chemical or biological data are available for E. sulcata, whether emphasizing the beneficial effects or the pharmacological security of this species. This study aims to evaluate myocardial contractility and to analyze angiotensin converting enzyme (ACE) and myosin ATPase activities associated with use of this essential oil. In addition, we evaluated the immunotoxicity of E. sulcata essential oil. Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR) were treated daily for 30 days (10 mg/kg of oil) to evaluate the isometric force of the papillary muscle, ACE measured by fluorimetry, and myosin ATPase activities by inorganic phosphate. Lymphocyte cultures were used to evaluate cytotoxicity, DNA damage, and mutagenicity of the essential oil. The results demonstrate that the treatment did not change the cardiac contraction force and did not alter the functioning of the sarcoplasmic reticulum, extrusion of the membrane calcium, or modify the membrane calcium channels or ß-adrenergic receptor activity. Tetanic contractions were potentiated in the SHR animals. Myosin ATPase activity was also increased in the SHR animals. Cardiac ACE activity was reduced in both animal strains, and the serum ACE was reduced only in the SHR animals. The essential oil did not cause cytotoxicity or mutagenicity and presented low DNA damage. Our results demonstrated that the essential oil does not change myocardial contractility and does not present relevant immunotoxicity
Asunto(s)
Animales , Masculino , Ratas , Aceites de Plantas/efectos adversos , Myrtaceae/efectos adversos , Eugenia/efectos adversos , Contracción Miocárdica/fisiología , Inhibidores de la Enzima Convertidora de Angiotensina/inmunología , Contracción MiocárdicaRESUMEN
Production of specific antibodies to haptens, especially antipeptides, without interference by carrier protein, is desirable. The bradykinin-potentiating peptides (BPPs) are a family of pyroglutamyl proline-rich oligopeptides with strong antihypertensive properties. In this work, the production of antibodies to BPPs by use of an efficient immunization protocol in mice genetically modified for the high antibody responsiveness (H(III) line) is described. Although it was possible to induce antibody production by single-dose administration of free BPPs, higher antibody titers were obtained in mice preimmunized with carrier protein before administration of peptides conjugated to this carrier. Interestingly, both mouse groups had a higher titer of IgG(1) than IgG(2a) isotypes, regardless of prior immunization with the carrier protein. However, a lower titer of IgG(2a) was observed in unprimed mice. A single band of about 27kDa corresponding to the BPP precursor protein was recognized by these antibodies in the cytosol of the Bothrops jararaca venom gland. This work proposes an efficient immunization protocol based on classic studies described for the hapten-carrier effect for generating specific antibodies against biologically active peptides.