The effects of histamine and other inflammatory mediators on the electrophysiology and intracellular free calcium ([Ca(2+)](i)) of human oviductal epithelial cells, grown as a polarized layer in primary culture, were studied. Transepithelial potential difference (PD) and short-circuit current (I(scc)) were recorded using a modified Ussing chamber. Resistance (R) was calculated from the measurements of PD and I(scc). Basally applied histamine produced transient increases in PD and I(scc) with a small decrease in R. The histamine effect was reduced by triprolidine (H(1) receptor antagonist) but was unaffected by H(2) (ranitidine) or H(3) (thioperamide) receptor antagonists. Blockers of Na(+), K(+), or Na(+)/K(+)/2Cl(-) channels did not affect histamine action. Blockers of Cl(-)/HCO(3)(-) channels or Ca(2+) channels reduced the histamine effect. Platelet activating factor (PAF), applied apically, increased PD and I(scc). Histamine produced a transient increase in fluorescence of Fura 2-AM dye, indicating an increase in [Ca(2+)](i). Triprolidine pretreatment inhibited histamine-stimulated [Ca(2+)](i) increase. Cimetidine, (H(2) receptor antagonist), ranitidine, or thioperamide reduced the histamine effect. Histamine increased contractions of both circular and longitudinal smooth muscles in oviduct segments, an effect that was antagonized by triprolidine or thioperamide but not by ranitidine. Histamine's action on Ca(2+) and Cl(-) movements may adversely affect oviductal fluid production and decrease fertility. PAF's effects on Cl(-) movements may be important for normal embryo transport.
function (FEV1, FEF25-75, total airway resistance at 5Hz: R5) and on salbutamol FEV1 recovery post histamine challenge. Comparisons were made between genotypes comprising one or two copies of Arg (i.e. ArgArg or ArgGly n = 15, FEV1 = 91.1%, FEF25-75 = 58.3%) vs. no copies of Arg (i.e. GlyGly n = 10, FEV1 = 94.1% FEF25-75 = 60.0%). Results Data are shown in table as change from baseline (i.e. pre vs. post propranolol as means and SEM) within each genotype. Within the Arg genotype there were significant effects of propranolol on FEV1, FEF25-75 and R5 as well as significant blunting of salbutamol response, while in the Gly genotype only salbutamol response was significant. However when comparing the Arg vs. Gly genotypes there were no significant differences for any of the outcomes. Conclusion Propranolol produces significant effects on pulmonary function and salbutamol response in the Arg genotype, although there were no significant differences between Arg and Gly genotypes. -2013-204457.344 Introduction and Objectives It is increasingly recognised that small airway dysfunction is associated with suboptimal asthma control. We have previously reported that b2-adrenoreceptor polymorphism at position 16 (i.e. Arg/Gly) is not related to FEV 1 or airway hyper-responsiveness in persistent asthmatics.
To determine the effects of spaceflight on the anterior pituitary gland, the adenohypophyses of rats after a 7-day spaceflight aboard the space shuttle Endeavor (STS-54) were investigated by histology, immunohistochemistry, morphometry, electron microscopy, and in situ hybridization and were compared with synchronous control rats. Morphometry revealed the corticotrophs of space-flown rats to be significantly enlarged, demonstrating 46-48% increases in mean cell, nuclear, and cytoplasmic areas. These corticotrophs also exhibited striking ultrastructural signs of heightened secretory activity. Furthermore, their expression of proopiomelanocortin mRNA, the transcript encoding the precursor protein from which adrenocorticotropic hormone is posttranslationally cleaved, was also significantly enhanced, a finding consistent with their hypersecretory state. Gonadotrophs also exhibited significant increments in mean nuclear, cell, and cytoplasmic areas of 22, 45, and 51%, respectively; however, they were not accompanied by ultrastructural evidence of increased secretory function. There were no morphological changes in somatotrophs, lactotrophs, or thyrotrophs, nor were there any significant changes in the overall frequency of any one adenohypophyseal cell type in comparison with control. The structural integrity of all adenohypophyseal secretory and vascular elements was preserved after spaceflight, as there was neither evidence of necrosis nor other forms of cellular injury in spaceflown specimens. Capillaries were patent, and neither endothelial damage nor thrombosis was noted. These data suggest that spaceflight is accompanied by a selective morphological response in the anterior pituitary, one characterized by hypertrophy of both corticotrophs and gonadotrophs and by enhanced endocrine activity of the former.
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