RESUMO
BACKGROUND: Nonspecific and delayed diagnosis of neurologic damage contributes to the development of neuropathies in patients with severe sepsis. The present study assessed the electrophysiologic parameters related to the excitability and conductibility of sciatic and vagus nerves during early stages of sepsis. MATERIALS AND METHODS: Twenty-four hours after sepsis induced by cecal ligation and puncture (CLP) model, sciatic and vagus nerves of septic (CLP group) and control (sham group) rats were removed, and selected electric stimulations were applied to measure the parameters of the first and second components of the compound action potential. The first component originated from fibers with motor and sensory functions (Types Aα and Aß fibers) with a large conduction velocity (70-120 m/s), and the second component originated from fibers (Type Aγ) with sensorial function. To evaluate the presence of sensorial alterations, the sensitivity to non-noxious mechanical stimuli was measured by using the von Frey test. Hematoxylin and eosin staining of the nerves was performed. RESULTS: We observed an increase of rheobase followed by a decrease in the first component amplitude and a higher paw withdrawal threshold in response to the application of von Frey filaments in sciatic nerves from the CLP group compared to the sham group. Differently, a decrease in rheobase and an increase in the first component amplitude of vagal C fibers from CLP group were registered. No significant morphologic alteration was observed. CONCLUSION: Our data showed that the electrophysiologic alterations in peripheral nerves vary with the fiber type and might be identified in the first 24 h of sepsis, before clinical signs of neuromuscular disorders.
RESUMO
BACKGROUND: Alpha-pinene (α-pinene) is a monoterpene commonly found in essential oils with gastroprotective activity obtained from diverse medicinal plants, including Hyptis species. The genus Hyptis (lamiaceae) consists of almost 400 species widespread in tropical and temperate regions of America. In the north and northeastern Brazil, some Hyptis species are used in traditional medicine to treat gastrointestinal disturbances. OBJECTIVE: The present study has investigated the gastoprotective effect of purified α-pinene in experimental gastric ulcer induced by ethanol and indomethacin in mice. MATERIALS AND METHODS: Gastric ulcers were induced in male Swiss mice (20-30 g) by oral administration of absolute ethanol or indomethacin 45 min after oral pretreatment with vehicle, standard control drugs or α-pinene (10, 30, and 100 mg/kg). One hour after the ulcerative challenges, the stomach were removed, and gastric lesions areas measured. The effects of α-pinene on the gastric juice acidity were determined by pylorus ligation model. The gastrointestinal motility and mucus depletion were determined by measuring the gastric levels of phenol red and alcian blue, respectively. Hematoxylin and eosin stained sections of gastric mucosa of the experimental groups were used for histology analysis. RESULTS: α-pinene pretreatment inhibited ethanol-induced gastric lesions, reduced volume and acidity of the gastric juice and increased gastric wall mucus (P < 0.05). Furthermore, we showed an interesting correlation between concentration of α-pinene and gastroprotective effect of Hyptis species (P Pearson = 0.98). CONCLUSION: Our data showed that the α-pinene exhibited significant antiulcerogenic activity and a great correlation between concentration of α-pinene and gastroprotective effect of Hyptis species was also observed.