bluuebunny/crossref_metadata_2025_split huggingface dataset:
α-Monoisostearyl glyceryl ether enhances percutaneous penetration of indometacin in-vivo
Authors: Suzuki Atsushi , Yamaguchi Tatsuyuki , Kawasaki Keiko , Hase Tadashi , Tokimitsu Ichiro 
Published: January 2003

Abstract
Molecules that reversibly remove the barrier resistance of skin enhance penetration. α-Monoisostearyl glyceryl ether (GE-IS) is a novel compound that can be used as a non-ionic surfactant and increases percutaneous penetration of indometacin in rat abdominal skin in-vitro. The present study investigated GE-IS-induced enhancement of indometacin penetration in-vivo. When 1% GE-IS in propylene glycol was applied to rat abdominal skin, serum and muscle concentrations of indometacin increased markedly. Anti-inflammatory activities of test solutions containing both indometacin and GE-IS were investigated in experimental models of acute and chronic inflammation. Application of indometacin with GE-IS to the skin produced greater inhibitory effects on carrageenan-induced rat paw oedema, UV-induced erythema in guinea-pigs, and adjuvant arthritis in rats, compared with application of indometacin alone. The results suggest that GE-IS enhances penetration in-vivo and improves the anti-inflammatory effects of indometacin in animal models. Thus, GE-IS might contribute to the development of cosmetic or medical formulations to improve transfer of bioactive substances to hypodermal sites.
Transbilayer transport of a propyltrimethylammonium derivative of diphenylhexatriene (TMAP-DPH) in bovine blood platelets and adrenal chromaffin cells
Authors: Kitagawa Shuji , Tachikawa Eiichi , Kashimoto Takashi 
Published: January 2003

Abstract
The membrane fluorescent probe N-((4-(6-phenyl-1,3,5-hexatrienyl)phenyl)propyl)trimethyl-ammonium (TMAP-DPH) has an additional three-carbon spacer between the fluorophore and the trimethylammonium substituent of 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH). As a basic study to clarify the transport mechanism of amphiphilic quaternary ammoniums, we observed the characteristics of the transbilayer transport of TMAP-DPH in bovine blood platelets and bovine adrenal chromaffin cells using the albumin extraction method. We compared these inward transport rates with those of TMA-DPH. TMAP-DPH crossed into the cytoplasmic layers of the membranes more slowly than TMA-DPH after rapid binding to the outer halves of the plasma membranes. The transport rate markedly depended on temperature. Time to reach the half-maximal incorporated amount of TMAP-DPH increased threefold accompanied by an increase in the concentration from 0.2 to 1.5 μm. The transport was stimulated significantly by various types of membrane perturbations such as modification of sulfhydryl-groups by N-ethylmaleimide and benzyl alcohol-induced increase in the fluidity of the lipid bilayer. The saturation phenomenon suggested the presence of the regulatory process in the transbilayer transport of TMAP-DPH.
Synthesis and radical scavenging of novel magnolol derivatives
Authors: Wang Yvonne , Li Chi-Yuan , Lin I-Hshin , Lee An-Rong , Hu Ming-Kuan 
Published: January 2003

Abstract
We have investigated the developdment of potential antioxidants based on magnolol, a naturally occurring biphenolic obtained from the bark of Magnolia officinalis. A series of aminomethylated derivatives of magnolol were synthesized under the aromatic Mannich reaction. In-vitro testing for diphenyl-p-picrylhydrazyl (DPPH) scavenging and chemiluminescence assays in whole cell models revealed that the pyrrolidyl-containing magnolols (2b (5,5′-diallyl-3-(pyrrolidin-1-ylmethyl)-biphenyl-2,2′-diol), 3a (5,5′-diallyl-3,3′-bis-(pyrrolidin-1-ylmethyl)-biphenyl-2,2′-diol) and 4c (5,5′-diallyl-3-(morphorin-4-ylmethyl)-3′-(pyrrolidin-1-ylmethyl)-biphenyl-2,2′-diol)) displayed promising free radical scavenging effects as compared with magnolol. The results from compound 4c indicated that the naturally occurring component was suitable to be a lead compound toward promising antioxidants.
Tocolytic activity of formoterol against premature delivery in mice
Authors: Shinkai N , Takasuna K , Takayama S 
Published: January 2003

Abstract
The tocolytic activity of formoterol (eformoterol), a long-acting potent β2-adrenoceptor agonist, was assessed in pregnant mice, with determination of uterine effects on the 15th and 16th days of gestation. For examination in the lipopolysaccharide-induced premature delivery model, osmotic pumps filled with formoterol or saline solution were implanted subcutaneously under the back skin. The mice were sacrificed 18–20 h thereafter, and the numbers of fetuses in the uteri and the newborn were counted. The uteri, amniotic membranes and placenta were also rapidly removed for determination of IL-6 concentrations. Furthermore, the effect of formoterol on IL-6 secretion from mouse amnion cells was determined. Formoterol and ritodrine inhibited contraction responses of isolated mouse uteri and their intravenous administration resulted in lowered uterine motility. Lipopolysaccharide (30 μg mL−1/mouse) induced premature delivery, attributable to increased IL-6 secretion, and formoterol suppressed this. Doses of 5–500 μg/mouse thus reduced the number of prematurely delivered newborn, and 50 μg/mouse also depressed IL-6 secretion. On histopathologic analysis, the marked oedema and slight haemorrhage in the mouse cervix induced by lipopolysaccharide were reduced by administration of the β2-adrenoceptor agonist. Neither formoterol (10−7–10−5 m) nor ritodrine (10−7–10−5 m) influenced spontaneous secretion of IL-6 in amnion cells. However, at 10−7 and 10−5 m, and 10−6 and 10−5 m, respectively, they inhibited lipopolysaccharide-induced IL-6 secretion and this inhibitory effect was competitively reversed by addition of ICI-118,551 (β2-adrenoceptor antagonist), but not atenolol (β1-adrenoceptor antagonist). These findings strongly suggest that formoterol can suppress premature delivery mediated by its actions on IL-6 secretion.
Inhibition of urinary bladder motility by a spinal action of U-50488H in rats
Authors: Gotoh Akinobu , Goto Kazuhiro , Sengoku Atsushi , Shirakawa Toshiro , Akao Yoshinobu , Fujisawa Masato , Okada Hiroshi , Arakawa Soichi , Sasaki Hiroshi , Kamidono Sadao 
Published: January 2003

Abstract
We examined the effect of a kappa agonist, U-50488H, upon the bladder motility of anaesthetized rats. The frequency of distension-induced rhythmic bladder contractions was reduced by the intravenous (10 mg kg−1) or intrathecal (10–100 μg) administration of U-50488H. The effect of intravenous U-50488H was inhibited by pre-treatment with nor-binaltorphimine (10 mg kg−1, s.c.). The inhibition of bladder contractions by intrathecal U-50488H (30 μg) was eliminated with the concomitant use of nor-binaltorphimine (10 mg kg−1, s.c.), and diminished by reserpine (4 mg kg−1, i.p.), yohimbine (10 μg, i.t.) or methysergide (20 μg, i.t.). The amplitude of bladder contractions induced by an electrical stimulation of the pontine micturition centre was not inhibited by intrathecal U-50488H (30 and 100 μg). These results suggested that a kappa agonist could inhibit micturition reflex as well as other opioids, and at least part of the inhibition was due to the diminishment of bladder sensation based on the activation of the descending monoaminergic systems through the spinal kappa-opioid receptors.
Rapid inhibition of the contraction of rat tail artery by progesterone is mediated by inhibition of calcium currents
Authors: Zhang Meili , Benishin Christina G , Pang Peter K T 
Published: January 2003

Abstract
Progesterone induced rapid relaxation of KCl-contracted tail artery helical strips from rats. The effect was dose dependent, with an IC50 (inhibitory concentration which produces 50% of the maximal response) of 8.9 μm progesterone. The actions of progesterone were not blocked by bicuculline, indicating that in this tissue the non-genomic actions of progesterone were not mediated via a γ-aminobutyric acid (GABA)-A receptor. Fura-2 was used to measure intracellular calcium levels ([Ca2+]i) in isolated vascular smooth muscle cells (VSMC). Incubation of cultured VSMC for 15 min with progesterone (10 μm) resulted in an inhibition of the KCl-induced [Ca2+]i increase. The whole-cell patch-clamp technique was used to examine Ca2+-channel currents in the membrane of isolated VSMC. Progesterone suppressed the L-type Ca2+-channel currents in cells held at a potential of − 40 mV. The effects of progesterone were quickly reversed by washout in all three experimental protocols suggesting that these effects on vascular tissues are non-genomic. The correlation of the effects on all these preparations, their time course and reversibility suggested that the rapid relaxation of the rat tail artery induced by progesterone is mediated at least in part by inhibition of L-type calcium channels, leading to inhibition of calcium responses in the VSMC of this tissue.
Function of pectoral fins in rainbow trout: behavioral repertoire and hydrodynamic forces
Authors: Drucker Eliot G. , Lauder George V. 
Published: January 2003

SUMMARYSalmonid fishes (trout, salmon and relatives) have served as a model system for study of the mechanics of aquatic animal locomotion, yet little is known about the function of non-axial propulsors in this major taxonomic group. In this study we examine the behavioral and hydromechanical repertoire of the paired pectoral fins of rainbow trout Oncorhynchus mykiss, performing both steady rectilinear swimming and unsteady maneuvering locomotion. A combination of kinematic analysis and quantitative flow visualization (using digital particle image velocimetry) enables identification of the propulsive roles played by pectoral fin motions. During constant-speed swimming (0.5 and 1.0 body length s-1), the pectoral fins remain adducted against the body. These fins are actively recruited, however, for a variety of maneuvering behaviors, including station holding in still water (hovering), low-speed(i.e. non-fast-start) turning, and rapid deceleration of the body during braking. Despite having a shallow pectoral-fin base orientation (the plesiomorphic teleost condition), trout are capable of rotating the fin base over 30° during maneuvering, which affords the fin an impressive degree of kinematic versatility. When hovering, the pectoral fins are depressed beneath the body and twisted along their long axes to allow anteroposterior sculling. During turning and braking, the fins undergo spanwise rotation in the opposite direction and exhibit mediolateral and dorsoventral excursions. Water velocity fields and calculated momentum flows in the wake of the pectoral fins reveal that positive thrust is not generated during maneuvering, except during the retraction half-stroke of hovering. Relatively large laterally directed fluid force (mean 2.7 mN) is developed during turning, whose reaction powers yawing rotation of the body (4-41° s-1). During deceleration, the wake-force line of action falls below the center of mass of the body, and this result supports a long-standing mechanical model of braking by fishes with ventrally positioned paired fins. Despite its traditional categorization as a propulsor of limited functional importance, the salmoniform pectoral fin exhibits a diverse locomotor repertoire comparable to that of higher teleostean fishes.
Corneal power and underwater accommodation in great cormorants(Phalacrocorax carbo sinensis)
Authors: Katzir Gadi , Howland Howard C. 
Published: January 2003

SUMMARY
In great cormorants (Phalacrocorax carbo sinensis), corneal refractive powers, determined by photokeratometry, ranged between 52.1 diopters (52.1 D) and 63.2 D. Photorefractive reflexes, determined by infrared video photorefraction, indicated that in voluntary dives the cormorants accommodate within 40-80 ms of submergence and with myopic focusing relative to the photorefractor attained when prey was approximately one bill length from the plane of the eye. Underwater, the pupils were not constricted and retained diameters similar to those in air. These results support previously reported capacities of lenticular changes in amphibious birds yet do not fully correspond with earlier reports in terms of the coupling of iris constriction with accommodation, and time course.
Requirement of Ca2+ on activation of sperm motility in euryhaline tilapiaOreochromis mossambicus
Authors: Morita M. , Takemura A. , Okuno M. 
Published: January 2003

SUMMARYEuryhaline tilapia Oreochromis mossambicus acclimates to the external spawning environment by modulating its mechanism for regulating sperm motility. Adaptation of sperm was performed by acclimating fish in various environments. In this paper, regulatory mechanisms of freshwater-acclimated tilapia were studied in detail. Tilapia sperm motility was vigorous in hypotonic conditions and decreased with increasing osmolality. Sperm motility was reduced in hypotonic conditions when extracellular Ca2+ was chelated; however, extracellular Ca2+ was not a major factor for motility activation since sperm were motile even when extracellular Ca2+ levels were nominally depleted by EGTA. The Ca2+indicator, fluo 3, showed that intracellular [Ca2+] increased on motility activation independently of extracellular [Ca2+],accompanied by swelling of the sperm neck region called the sleeve structure. Intracellular [Ca2+] was not increased under hypertonic conditions,in which sperm were immotile, even on addition of extracellular Ca2+. It is possible that Ca2+ is stored in the neck region. Demembranated sperm were reactivated in the presence of Ca2+, but cAMP failed to reactivate the motility. Furthermore, we detected phosphorylation and dephosphorylation of three proteins at serine and threonine residues on motility activation. It is likely that hypotonic shock causes an increase in intracellular [Ca2+] that activates motility activation via phosphorylation of some flagellar proteins.
Characterization of ryanodine receptor and Ca2+-ATPase isoforms in the thermogenic heater organ of blue marlin (Makaira nigricans)
Authors: Morrissette Jeffery M. , Franck Jens P. G. , Block Barbara A. 
Published: January 2003

SUMMARY
A thermogenic organ is found beneath the brain of billfishes(Istiophoridae), swordfish (Xiphiidae) and the butterfly mackerel(Scombridae). The heater organ has been shown to warm the brain and eyes up to 14°C above ambient water temperature. Heater cells are derived from extraocular muscle fibers and express a modified muscle phenotype with an extensive transverse-tubule (T-tubule) network and sarcoplasmic reticulum (SR)enriched in Ca2+-ATPase (SERCA) pumps and ryanodine receptors(RyRs). Heater cells have a high mitochondria content but have lost most of the contractile myofilaments. Thermogenesis has been hypothesized to be associated with release and reuptake of Ca2+. In this study,Ca2+ fluxes in heater SR vesicles derived from blue marlin(Makaira nigricans) were measured using fura-2 fluorescence. Upon the addition of MgATP, heater SR vesicles rapidly sequestered Ca2+. Uptake of Ca2+ was thapsigargin sensitive, and maximum loading ranged between 0.8 μmol Ca2+ mg-1 protein and 1.0μmol Ca2+ mg-1 protein. Upon the addition of 10 mmol l-1 caffeine or 350 μmol l-1 ryanodine, heater SR vesicles released only a small fraction of the loaded Ca2+. However, ryanodine could elicit a much larger Ca2+ release event when the activity of the SERCA pumps was reduced. RNase protection assays revealed that heater tissue expresses an RyR isoform that is also expressed in fish slow-twitch skeletal muscle but is distinct from the RyR expressed in fish fast-twitch skeletal muscle. The heater and slow-twitch muscle RyR isoform has unique physiological properties. In the presence of adenine nucleotides, this RyR remains open even though cytoplasmic Ca2+ is elevated, a condition that normally closes RyRs. The fast Ca2+sequestration by the heater SR, coupled with a physiologically unique RyR, is hypothesized to promote Ca2+ cycling, ATP turnover and heat generation. A branch of the oculomotor nerve innervates heater organs, and, in this paper, we demonstrate that heater cells contain large `endplate-like'clusters of acetylcholine receptors that appear to provide a mechanism for nervous control of thermogenesis.
Vacuolar-type proton pump in the basolateral plasma membrane energizes ion uptake in branchial mitochondria-rich cells of killifishFundulus heteroclitus, adapted to a low ion environment
Authors: Katoh Fumi , Hyodo Susumu , Kaneko Toyoji 
Published: January 2003

SUMMARYWe examined the involvement of mitochondria-rich (MR) cells in ion uptake through gill epithelia in freshwater-adapted killifish Fundulus heteroclitus, by morphological observation of MR cells and molecular identification of the vacuolar-type proton pump (V-ATPase). MR cell morphology was compared in fish acclimated to defined freshwaters with different NaCl concentrations: low (0.1 mmol l-1)-, mid (1 mmol l-1)-and high (10 mmol l-1)-NaCl environments. MR cells, mostly located on the afferent-vascular side of the gill filaments, were larger in low- and mid-NaCl environments than in the high-NaCl environment. Electron-microscopic observation revealed that the apical membrane of well-developed MR cells in low- and mid-NaCl environments was flat or slightly projecting, and equipped with microvilli to expand the surface area exposed to these environments. On the other hand, in the high-NaCl environment, the apical membrane was invaginated to form a pit, and MR cells often formed multicellular complexes with accessory cells, although the NaCl concentration was much lower than that in plasma. We cloned and sequenced a cDNA encoding the A-subunit of killifish V-ATPase. The deduced amino acid sequence showed high identity with V-ATPase A-subunits from other vertebrate species. Light-microscopic immunocytochemistry, using a homologous antibody, revealed V-ATPase-immunoreactivity in Na+/K+-ATPase-immunoreactive MR cells in low-NaCl freshwater, whereas the immunoreactivity was much weaker in higher NaCl environments. Furthermore, immuno-electron microscopy revealed V-ATPase to be located in the basolateral membrane of MR cells. These findings indicate that MR cells are the site responsible for active ion uptake in freshwater-adapted killifish, and that basolaterally located V-ATPase is involved in the Na+ and/or Cl- absorbing mechanism of MR cells.
Involvement of Gq/11 in signal transduction in the mammalian vomeronasal organ
Authors: Wekesa Kennedy S. , Miller Stephanie , Napier Audrey 
Published: January 2003

SUMMARYSocial behaviors of most mammals are profoundly affected by pheromones. Pheromones are detected by G-protein coupled receptors in the vomeronasal organ (VNO). To investigate the role of Gαq/11 in vomeronasal signal transduction pathways, microvillar membranes from murine VNO were prepared. Incubation of such membranes from prepubertal females with adult male urine results in an increase in production of inositol-(1,4,5)-trisphosphate (IP3). This stimulation is mimicked by GTPγS, blocked by GDPβS and is tissue specific. Furthermore, use of bacterial toxins such as pertussis that lead to ADP-ribosylation of the G-protein alpha subunits of Go and Gi2 do not block the increase in IP3 levels but U-73122, a PLC inhibitor, blocks the production of IP3. Studies with monospecific antibodies revealed the presence of three G-proteins, Gαo, Gαi2and Gαq/11-related protein, in vomeronasal neurons,concentrated on their microvilli. Our observations indicate that pheromones in male urine act on vomeronasal neurons in the female VNO via a receptor-mediated, Gαq/11-protein-dependent increase in IP3 levels.
Odor localization requires visual feedback during free flight inDrosophila melanogaster
Authors: Frye Mark A. , Tarsitano Michael , Dickinson Michael H. 
Published: January 2003

SUMMARYAdult fruit flies follow attractive odors associated with food and oviposition sites through widely varied visual landscapes. To examine the interaction between olfactory and visual cues during search behavior, we recorded three-dimensional flight trajectories as individuals explored controlled sensory landscapes. When presented with the source of an attractive odor invisibly embedded in the floor of a 1 m arena, flies spend most of their time hovering back and forth over the source when flying within a randomly textured visual background but fail to localize the source when searching within a uniform white surround. To test whether flies are associating unique features of the visual background with the strength of odor cues, we flew them within arenas containing evenly spaced vertical stripes. Flies readily localized the odor when flying within visual landscapes lacking azimuthal landmarks provided that vertical edges were present. Flies failed to localize odor when flying within a background pattern consisting of horizontal stripes. These results suggest that, whereas flies do not require spatially unique visual patterns to localize an odor source, they do require visual feedback generated by vertical edges. Quantitative shifts in several components of flight behavior accompanied successful odor localization. Flies decrease flight altitude, turn more often and approach visually textured walls of the arena near an odor source. A simple model based on the statistics of flight behavior supports the hypothesis that a subtle influence on these behaviors is sufficient to lead a fly to its food.
Do familiar landmarks reset the global path integration system of desert ants?
Authors: Collett M. , Collett T. S. , Chameron S. , Wehner R. 
Published: January 2003

SUMMARY
It is often suggested that animals may link landmark memories to a global coordinate system provided by path integration, thereby obtaining a map-like representation of familiar terrain. In an attempt to discover if desert ants form such associations we have performed experiments that test whether desert ants recall a long-term memory of a global path integration vector on arriving at a familiar food site. Ants from three nests were trained along L-shaped routes to a feeder. Each route was entirely within open-topped channels that obscured all natural landmarks. Conspicuous artificial landmarks were attached to the channelling that formed the latter part of the route. The homeward vectors of ants accustomed to the route were tested with the foodward route,either as in training, or with the first leg of the L shortened or extended. These ants were taken from the feeder to a test area and released, whereupon they performed a home vector. If travelling the latter part of a familiar route and arriving at a familiar food site triggers the recall of an accustomed home vector, then the home vector should be the same under both test conditions. We find instead that the home vector tended to reflect the immediately preceding outward journey. In conjunction with earlier work, these experiments led us to conclude in the case of desert ants that landmark memories do not prime the recall of long-term global path integration memories. On the other hand, landmark memories are known to be linked to local path integration vectors that guide ants along a segment of a route. Landmarks thus seem to provide procedural information telling ants what action to perform next but not the positional information that gives an ant its location relative to its nest.