Autoregulation of the ciliary beat frequency (CBF) has been proposed as the mechanism used by epithelial ciliated cells to maintain the CBF and prevent the collapse of mucociliary transport under conditions of varying mucus viscosity. Despite the relevance of this regulatory response to the pathophysiology of airways and reproductive tract, the underlying cellular and molecular aspects remain unknown. Hamster oviductal ciliated cells express the transient receptor potential vanilloid 4 (TRPV4) channel, which is activated by increased viscous load involving a phospholipase A2–dependent pathway. TRPV4-transfected HeLa cells also increased their cationic currents in response to high viscous load. This mechanical activation is prevented in native ciliated cells loaded with a TRPV4 antibody. Application of the TRPV4 synthetic ligand 4α-phorbol 12,13-didecanoate increased cationic currents, intracellular Ca2+, and the CBF in the absence of a viscous load. Therefore, TRPV4 emerges as a candidate to participate in the coupling of fluid viscosity changes to the generation of the Ca2+ signal required for the autoregulation of CBF.

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The oviduct acts as a functional sperm reservoir in many mammalian species. Both binding and release of spermatozoa from the oviductal epithelium are mainly modulated by sperm capacitation. Several molecules from oviductal fluid are involved in the regulation of sperm function. Anandamide is a lipid mediator involved in reproductive physiology. Previously, we demonstrated that anandamide, through activation of the cannabinoid receptor type 1 (CB1), promotes sperm release from bovine oviductal epithelial cells, and through CB1 and the transient receptor potential vanilloid 1 (TRPV1), induces sperm capacitation. Herein we investigate co-activation between CB1 and TRPV1, and Ca(2+) influx as part of the mechanism of action of anandamide during sperm release from oviductal cells. Our results indicate that in the absence of Ca(2+) anandamide failed to release spermatozoa from oviductal epithelial cells. Additionally, sperm release promoted by cannabinoid and vanilloid agonists was abolished when the spermatozoa were preloaded with BAPTA-AM, a Ca(2+) chelator. We also determined Ca(2+) levels in spermatozoa preloaded with FURA2-AM co-cultured with oviductal cells and incubated with different cannabinoid and vanilloid agonists. The incubation with different agonists induced Ca(2+) influx, which was abolished by CB1 or TRPV1 antagonists. Our results also suggest that a phospholypase C (PLC) might mediate the activation of CB1 and TRPV1 in sperm release from the bovine oviduct. Therefore, our findings indicate that anandamide, through CB1 and TRPV1 activation, is involved in sperm release from the oviductal reservoir. An increase of sperm Ca(2+) levels and the PLC activation might be involved in anandamide signaling pathway.

BackgroundThe objective was to perform a systematic review in order to describe the relationship between asthma and sleep-disordered breathing (SDB) in children, especially regarding the impact of treatment and management.MethodsWe performed an electronic search in MEDLINE, EMBASE, and LILACS database. Study inclusion criteria were the following: 1) studies that examined the relationship between asthma/wheezing and SDB/obstructive sleep apnea (OSA); and 2) studies conducted in children <18 years of age. Primary outcomes were the prevalence of asthma and SDB, the tests used for diagnosis, and the influence of their treatment and management.ResultsOne thousand and twenty studies were identified, among which 32 were selected (n=143,343 children; 51% males; age [mean ± standard deviation] 8.4±2.5 years). Most studies (n=26) diagnosed SDB using questionnaires or clinical history. Nine studies performed a sleep study for diagnosing OSA. The diagnosis of asthma was based on clinical history (n=16), previous medical diagnosis (n=4), questionnaires (n=12), and spirometry (n=5). Children with asthma were more likely to develop habitual snoring and OSA, and children with SDB were more likely to develop asthma. Moreover, asthma was associated with more severe OSA, and the presence of SDB was associated with severe asthma. Treatment of SDB with adenotonsillectomy was associated with significant asthma improvement.ConclusionThe relationship between asthma and SDB appears to be bidirectional, and adenotonsillectomy appears to improve asthma control. Future trials on how asthma treatment could impact on SDB are needed.

Palabras clave autores Actitudes ambientales, antropocentrismo, conducta ecológica, satisfacción vital, malestar personal. Palabras clave descriptores Educación ambiental, medio ambiente natural, bienestar psicológico, modelo factorial confirmatorio.