Effect of menthol on cytosolic Ca2+ levels in canine airway epithelium in culture

Intracellular Ca2+ concentration ([Ca2+]i) in canine cultured tracheal epithelium in response to cyclic alcohols was measured by a fura-2 method. Menthol rapidly increased [Ca2+]i in a concentration-dependent fashion, the maximal increase from the baseline levels and the concentration of menthol required to produce a half-maximal effect (EC50) being 148 +/- 23 nM (mean +/- SE, p < 0.001) and 0.3 mM, respectively, whereas other cyclic alcohols including menthone and cyclohexanol had no effect. The menthol-induced increase in [Ca2+]i was not affected by verapamil but partially inhibited by low Ca2+ medium in the presence of EGTA. These results indicate that menthol specifically increases cytosolic Ca2+ in airway epithelium, which may be derived from intracellular Ca2+ stores.

Spinal cord tumor appearing as unusual pain

STUDY DESIGN

The authors report two cases of spinal cord tumors characterized by unusual pain, which is recurrent abdominal pain or cervical angina.

METHODS

These unusual pains were improved after removal of tumors in the patients.

CONCLUSIONS

The authors conclude that the pain was caused by vascular compression, bleeding in the tumor, or incomplete block of the cerebrospinal fluid flow. They recommend the use of osteoplastic laminectomy, because anatomic structure and spinal function should be preserved in young patients.

[Recombinant human erythropoietin (KRN5702) therapy for autologous blood transfusion in patients with rheumatoid arthritis undergoing joint replacement surgery--a multicenter phase II clinical trial]

In order to evaluate the effect of recombinant human erythropoietin (rHuEPO) on autologous blood transfusion in patients with rheumatoid arthritis (RA), we performed a phase II clinical trial in 65 RA patients undergoing elective surgery. rHuEPO was administered subcutaneously once a week and after observing erythropoiesis, autologous blood was collected. Fifty-seven of the 58 patients who completed treatment responded to rHuEPO and could donate more than 400 ml of autologous blood. Among them, 23 out of 28 patients undergoing total hip arthroplasty, 27 out of 28 undergoing total knee arthroplasty and 1 out of 1 undergoing spinal surgery did not need homologous blood transfusion perioperatively. During rHuEPO treatment, no significant changes of clinical parameters of RA activity were observed. Two patients discontinued the treatment because of mild and transient side effects. These results indicate that subcutaneous rHuEPO is safe and effective in eliminate the need for homologous blood transfusion, even in anemic RA patients undergoing elective orthopedic surgery.

Stimulation by menthol of Cl secretion via a Ca(2+)-dependent mechanism in canine airway epithelium

1. To investigate the effect of menthol on airway epithelial ion transport function, we studied the bioelectrical properties of canine cultured tracheal epithelium by Ussing's short-circuit technique in vitro. 2. Addition of menthol (10(-3) M) to the mucosal but not the submucosal solution increased the short-circuit current (Isc) from 6.2 +/- 0.9 to 14.0 +/- 2.2 microA cm-2 (P < 0.001), and this effect was accompanied by increases in transepithelial potential difference and conductance. The response was dose-dependent, with the maximal increase from the baseline value and the concentration required to produce a half-maximal effect (EC50) being 6.4 +/- 0.9 microA cm-2 (P < 0.001) and 40 microM, respectively. 3. Other cyclic alcohols, including menthone and cyclohexanol, had no effect on the electrical properties. 4. The menthol-induced increase in Isc was not altered by pretreatment of the cells with amiloride, indomethacin, or propranolol but was abolished by diphenylamine-2-carboxylate, furosemide or substitution of Cl with iodide in the medium. 5. Menthol (10(-3) M) increased cytosolic levels of free calcium ([Ca2+]i) from 98 +/- 12 to 340 +/- 49 nM (P < 0.01) in fura-2-loaded tracheal epithelium but did not affect the intracellular adenosine 3',5'-cyclic monophosphate content. 6. These results suggest that menthol stimulates Cl secretion across airway epithelium, probably through a Ca(2+)-dependent mechanism, and might thus influence mucociliary transport in the respiratory tract.

Relationship between basal metabolic rate, thermogenic response to caffeine, and body weight loss following combined low calorie and exercise treatment in obese women

To clarify whether there were any differences in basal metabolic rate (BMR) and thermogenic response to caffeine in individual obese women, and if so, whether such differences affected weight loss, the basal and resting metabolic rates at 30 min after a caffeine loading test (4 mg/kg ideal body weight, per os) were measured in 136 obese women and ten lean age-matched controls. The obese subjects were then asked to follow a combined low calorie diet and exercise regimen. There were no differences in the BMR and thermogenic responses to caffeine between the obese and lean groups. However, the BMR and the thermogenic responses to caffeine varied widely in obese subjects. After two months of treatment, body weight and percentage body fat in obese women were significantly (P < 0.001) reduced. There were significant correlations between the BMR and body weight loss (r = 0.3621, P < 0.001), between BMR/lean body mass and body weight loss (r = 0.3196, P < 0.001) and between the thermogenic response to caffeine and body weight loss (r = 0.6943, P < 0.001). When the criterion of a BMR less than 3.10 kJ/min (less than two standard deviations below the mean of the age-matched lean control) was used to define an obese group with reduced BMR, there were 30 obese subjects in this group, and their body weight was significantly decreased by treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

The alpha/beta-adrenergic receptor blocker arotinolol activates the thermogenesis of brown adipose tissue in monosodium-L-glutamate-induced obese mice

We have found previously that arotinolol, an alpha/beta-adrenergic blocker, increases blood flow in brown adipose tissue (BAT) in a similar extent as BRL 26830A, a beta 3-adrenoceptor agonist. We tested the hypothesis that arotinolol activates thermogenesis in BAT, leading to weight loss in monosodium-L-glutamate-induced (MSG-induced) obese mice and saline-treated controls. Six weeks of standard animal feed (CE-2) containing arotinolol hydrochloride (350 mg/kg CE-2), which reduced mean blood pressure in MSG-treated mice, significantly increased the mitochondrial protein content in BAT, and activated the specific and total binding of guanosine-5'-diphosphate (GDP) in BAT mitochondria, leading to a reduction of obesity in both MSG- and saline-treated mice vs. the control groups fed with CE-2 diet alone. However, six weeks of CE-2 diet containing propranolol hydrochloride (525 mg/kg CE-2) a non-selective beta-blocker, markedly reduced the specific and total binding of GDP in BAT mitochondria, leading to weight gain in both MSG- and saline-treated mice. These findings support the hypothesis, that arotinolol activates BAT thermogenesis, leading to weight loss.

Local secretion of corticotropin-releasing hormone by enterochromaffin cells in human colon

BACKGROUND/AIMS

Corticotropin-releasing hormone (CRH) is a regulator of the hypothalamic-pituitary-adrenal axis and a coordinator of the gastrointestinal response to stress. In addition to its central effects, CRH has peripheral effects on the immune system. CRH is present in several human tissues, such as the brain, spinal cord, adrenal medulla, lung, liver, peripheral blood leukocytes, as well as the gastrointestinal tract. The current study examined the local production of CRH in the normal human colon.

METHODS

Normal human colonic tissues obtained by endoscopic biopsy were immunostained with anti-CRH and anti-5-hydroxytryptamine antibody and analyzed for CRH messenger (m)RNA by a reverse-transcribed polymerase chain reaction method and by in situ hybridization.

RESULTS

Immunoreactive CRH and CRH mRNA were detected in the colonic mucosal cells in the neighborhood of the base of the crypts. The mucosal cells that expressed CRH mRNA also immunostained with anti-5-hydroxytryptamine antibody.

CONCLUSIONS

Normal human colonic mucosal enterochromaffin cells produce CRH. CRH in the colonic mucosa may play a role in the modulation of the intestinal immune system and/or other gastrointestinal functions basally during stressful conditions.

Movement of carboxyfluorescein across the isolated rabbit iris-ciliary body

The movement of carboxyfluorescein across the isolated iris-ciliary body of the albino rabbit was analyzed using an Ussing chamber under short-circuit conditions with carboxyfluorescein concentrations ranging from 10 to 100 microM. At a concentration of 50 microM, the outward permeability (from the aqueous to the stromal side) was 4.0 +/- 0.2 x 10(-6) cm/sec and the inward permeability (from the stromal to the aqueous side) was 1.3 +/- 0.2 x 10(-6) cm/sec (Mean +/- SE, N = 6). The former was significantly greater than the latter (P < 0.001). Inward movement of carboxyfluorescein showed a linear increase in relation to the concentrations tested. Neither ouabain (100 microM), 2,4-dinitrophenol (10 microM) nor probenecid (100 microM) significantly inhibited the inward movement of carboxyfluorescein. The net outward movement of carboxy-fluorescein became saturated, as concentration was increased, and a Lineweaver--Burke plot gave an apparent Km of 28 microM and Vmax of 0.67 x 10(-9) mole/hr/cm2. In addition, outward carboxyfluorescein movement was significantly inhibited by ouabain (100 microM), 2,4-dinitrophenol (10 microM), probenecid (100 microM), iodipamide (1.0 mM), hippurate (1.0 mM), low temperature or low external Na+ concentration. These results suggest that outward carboxyfluorescein movement across the tissue largely depends on carrier-mediated active transport, while inward movement occurs by passive diffusion.

Functional participation of the IL-2 receptor gamma chain in IL-7 receptor complexes

The gamma chain of the interleukin-2 (IL-2) receptor is shared with the functional IL-4 receptor and is causatively related to X-linked severe combined immunodeficiency (XSCID), which is ascribed to a profound T cell defect. Studies with monoclonal antibodies specific for the IL-2 receptor gamma chain showed that the gamma chain participates in the functional high-affinity receptor complexes for IL-7 that are involved in the differentiation of T and B cells. Participation of the gamma subunit in more than one receptor may enable the elucidation of the mechanisms of XSCID development and lymphocyte differentiation.

Supra- and juxtatrigeminal inhibitory premotor neurons with bifurcating axons projecting to masseter motoneurons on both sides

Inhibitory neurons participating in the bilateral disynaptic inhibition of jaw-closing motoneurons by stimulation of unilateral trigeminal sensory branches were searched for in the reticular formation around the trigeminal motor nucleus in cats anaesthetized with pentobarbital. Extracellular recordings were made from neurons which responded orthodromically after a monosynaptic latency to single shock stimulation of the ipsilateral infraorbital and/or inferior alveolar nerves. Direct inhibitory connection with contralateral masseter motoneurons was demonstrated in reticular neurons by the spike-triggered averaging technique, i.e., by averaging the intracellular potentials of a contralateral masseter motoneuron with respect to spontaneously occurring spikes of a reticular interneuron. By intraaxonal injection of neurobiotin, electrophysiologically identified inhibitory premotor reticular neurons were found to project to and to terminate in the trigeminal motor nuclei on both sides. Termination in the contralateral motor nucleus was demonstrated for four neurons that showed the peripheral input pattern stated above. The results provide hard evidence for contralaterally projecting interneurons in the reticular formation, participating in peripherally evoked disynaptic inhibition of masseter motoneurons on the contralateral side. Given the previously reported findings that the supratrigeminal region contains neurons which project to the ipsilateral motor nucleus and mediate disynaptic inhibition of masseter motoneurons, it is suggested that the supratrigeminal region contains bilaterally projecting interneurons, mediating peripherally evoked disynaptic inhibition of masseter motoneurons on both sides.

New teleocidin-related metabolites, (-)-7-geranylindolactam V and blastmycetin F, from Streptoverticillium blastmyceticum

Two new teleocidin-related metabolites, (-)-7-geranylindolactam-V [2] and blastmycetin F [3], were isolated from fermentation broths of the actinomycete Streptoverticillium blastmyceticum NA34-17, and their structures were determined by spectroscopic methods. Compound 2 bound strongly to phorbol ester receptors in a mouse epidermal particulate fraction, suggesting that it is a potent in vivo tumor promoter comparable to teleocidins A-1 [4] and B-4 [5].

Antioxidant properties of bromocriptine, a dopamine agonist

It has been suggested that free radicals may adversely influence the pathogenesis of Parkinson's disease. We conducted this study to determine whether bromocriptine, an agent widely used for treating parkinsonism, possesses antioxidant effects. Bromocriptine scavenged superoxide produced from a superoxide generating system (hypoxanthine-xanthine oxidase) by the spin-trapping method using electron spin resonance. Bromocriptine had a strong scavenging effect on the 5,5-dimethyl-1-pyrroline-N-oxide hydroxide signal produced from Fenton's reaction. Bromocriptine also attenuated the stable free radical diphenyl-p-picrylhydrazyl signal. This drug inhibited the autooxidation of rat brain homogenates in a dose-dependent manner in vitro. Autooxidation of brain homogenates collected from rats treated with bromocriptine (2.5 mg/kg, i.p., daily for 3 days) was significantly reduced as compared with values in untreated rat homogenates. These observations suggest that bromocriptine is a free radical scavenger and a potent antioxidant.

Effect of platelet-activating factor on intracellular free calcium in cow tracheal epithelium

The effect of platelet activating factor (PAF) on the intracellular cytosolic levels of free calcium ([Ca2+]i) was studied in cultured epithelium from cow trachea. In fura-2-loaded cells, PAF (10(-9) to 10(-5) M), but not lyso-PAF, increased [Ca2+]i in a concentration-dependent manner, from 106 +/- 15 to 270 +/- 40 nM (P < 0.05). This [Ca2+]i response consisted of a transient increase that peaked within 15 s after addition and a subsequent sustained elevation that reached a plateau after 1 min. The potency for the sustained response was greater by approximately 1 log U than that for the transient response. Preincubation of the cells with the PAF receptor antagonist CV6209 (10(-6) M) inhibited the increase in [Ca2+]i. Ca(2+)-free medium (2 mM EGTA) totally abolished the sustained response to PAF, but it only partially inhibited the transient response. Verapamil (10(-5) M) also largely inhibited the sustained response. Moreover, PAF transiently increased inositol triphosphate (IP3) levels, peaking 10 s after addition. These data suggest that (1) a PAF-induced increase in [Ca2+]i is mediated via PAF receptors, (2) PAF causes both transient [Ca2+]i release from intracellular stores through IP3 production and sustained [Ca2+]i influx from extracellular solution, and (3) Ca2+ influx may be a major pathway of PAF-induced increase in [Ca2+]i in cow tracheal epithelium.

Effects of aldehyde-modified proteins on mesangial cell-matrix interaction

We examined the effect of aldehyde-modified matrix macromolecules on mesangial cell function in vitro, using incubated rat glomerular mesangial cells. Laminin and fibronectin were modified by incubation for 24 h with 50 mM glycolaldehyde (GA), a highly reactive cross-linking glycation product, with or without equimolar aminoguanidine. GA-modified laminin and fibronectin caused marked inhibition of cell adhesion. Cell spreading was reduced on the GA-modified laminin. In contrast, the GA-modified fibronectin had no effect on cell spreading. The study of thymidine incorporation by mesangial cells showed that the GA-modified fibronectin had a diminished mitogenic activity against cells. The content of advanced glycation end-product (AGE), which was determined by fluorescence at 370 nm excitation and 440 nm emission wavelength, increased and intermolecular cross-links appeared in the GA-modified proteins. To a large extent, aminoguanidine restored the structural alterations and functional deteriorations described above. We conclude that GA-modified matrix proteins diminish their functional properties against mesangial cells and affect cellular functions.

Analysis of longitudinal distribution of pulmonary vascular resistance by use of a five element lumped model

To analyze longitudinal distribution of pulmonary vascular resistance, we proposed a five element lumped model which partitioned pulmonary circulation into pulmonary arterial, middle and pulmonary venous segment. The validity and anatomical correlation of the model were tested in an isolated, perfused, canine lung lobe preparation with inflow/outflow occlusion techniques. With arterial occlusion, pulmonary arterial pressure fell rapidly and then exponentially. With venous occlusion, pulmonary venous pressure rose suddenly and then exponentially. Theoretical pressure profiles produced by computer simulation of the model well approximated the general characteristics of the experimental traces. Serotonin increased the pressure gradient across the pulmonary arterial segment (delta Pa), whereas histamine increased the gradient across the pulmonary venous segment (delta Pv). Neither drug altered the gradient across the middle segment (delta Pm). The results suggest that the lumped model is a useful concept to understand the longitudinal distribution of pulmonary vascular resistance, and that delta Pa, delta Pm and delta Pv reflect the resistance distribution of anatomical pulmonary arteries, alveolar vessels and pulmonary veins, respectively.

Creatol, a creatinine metabolite, as a useful determinant of renal function

Analysis of creatol (CTL, 5-hydroxycreatinine), an oxidative creatinine (Cr) metabolite, in serum and urine of human subjects has indicated that CTL is a useful determinant of renal function. The existence itself of serum CTL (s-CTL) could be a diagnostic sign for chronic renal failure (CRF): in all normal subjects, s-CTL was undetectable, but s-CTL was detectable in sera of all patients with CRF (s-Cr: > 2.0 mg/dl). And the s-CTL values increased in proportion to the severity of CRF in such patients. Furthermore, the molar ratio (CTL/Cr) in both urine and serum increased significantly in proportion to the severity of CRF. Our results indicated not only hyperproduction of CTL but also higher oxygen stress in patients according to the progression of CRF. The diagnostic importance of the CTL value and the CTL/Cr ratio are discussed.

Changes in tissue antioxidant enzyme activities and lipid peroxides in endotoxin-induced multiple organ failure

Intravenous administration of bacterial endotoxin (lipopolysaccharide: LPS) induces shock and disseminated intravascular coagulation in rats. Our report here shows that LPS-administered rats (10 mg/100 g) develop tissue injuries and functional disorders in multiple vital organs. In the present study, we investigated changes in tissue antioxidant enzyme activities, neutrophil sequestration, and lipid peroxides in multiple organs (lung, stomach, small intestine for antioxidant enzyme activities and neutrophil sequestration; lung, stomach, small intestine, liver, abdominal aorta for lipid peroxides) of LPS-treated rats. LPS-treated animals morphologically revealed pulmonary interstitial edema, alveolar hemorrhage, and mucosal hemorrhage in the small intestine 45 min after LPS administration. Blood samples withdrawn from LPS-treated animals exhibited increases in serum amylase, blood urea nitrogen, creatinine, and transaminase levels up to 180 min post-LPS infusion. LPS-treated animals showed a significant increase in tissue myeloperoxidase (MPO) activities of the lung, but not of the small intestine and stomach 45 min after LPS infusion. Thiobarbituric acid reactive substances (TBARS) in the lung, small intestine, stomach, liver, and abdominal aorta significantly increased at 45 min post-LPS-infusion. Tissue superoxide dismutase (SOD) activities of the LPS-treated animals demonstrated a significant decrease in the lung, which suffered from severe insults and neutrophil sequestration; no significant change in the small intestine, which suffered from morphological insults without neutrophil sequestration, and a significant increase in the stomach, which showed no histological impairment, at 180 min post-LPS administration. Glutathione peroxidase (GSH-PX) activities of the lung and small intestine showed no significant change in LPS-treated rats, while those of the stomach revealed a marked increase.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant human granulocyte colony-stimulating factor augments cytotoxicity of OK-432-induced polymorphonuclear leukocytes

Polymorphonuclear leukocytes (PMNs) recovered from the peritoneal cavity of mice treated with the streptococcal preparation OK-432, exhibited strong cytotoxicity after the in vitro addition of Nocardia rubra cell wall skeleton (N-CWS). In this study, we investigated whether recombinant human granulocyte colony-stimulating factor (rhG-CSF) could augment the cytotoxicity of OK-432-induced PMNs after the addition of N-CWS in vitro. PMNs recovered from the peritoneal cavity of 8- to 10-week-old, male C3H/He mice induced by intraperitoneal (i.p.) injection of 50 KE/kg (1 KE = 0.1 mg) of OK-432 were used in a 51Cr release assay against MM46 mammary carcinoma cells. While addition of rhG-CSF in vitro did not augment the cytotoxicity of OK-432-induced PMNs, marked augmentation of the cytotoxicity of OK-432-induced PMNs was observed following a single subcutaneous (s.c.) or i.p. injection of 125 micrograms/kg of rhG-CSF. The effect of in vivo administered rhG-CSF was dependent on the timing of the injection with respect to OK-432 administration and differed from s.c. or i.p. injections. Interestingly, the cytotoxicity of OK-432-induced PMNs was rather weak following consecutive s.c. or i.p. administration of rhG-CSF for 7-14 days. H2O2 is likely involved in mediating the cytotoxicity of OK-432-induced PMNs since activity was significantly reduced by the in vitro addition of low concentration of catalase. Generation of H2O2 by the PMNs correlated with cytotoxicity. These results suggest that in vivo administration of rhG-CSF augments the cytotoxicity of OK-432-induced PMNs in a time dependent fashion and that H2O2 plays an important role in mediating their cytotoxicity.

Effect of nicotine on sympathetic nervous system activity of mice subjected to immobilization stress

We tested the hypothesis that nicotine possesses an antistress action by measuring the turnover of norepinephrine (NE), a reliable indicator of sympathetic nervous system activity, in the interscapular brown adipose tissue (IBAT) and heart of mice treated with nicotine injections, immobilization stress, or nicotine + immobilization stress, vs. untreated controls. Nicotine enhanced the sympathetic activity in the IBAT and heart, and induced a loss of body weight. Immobilization-related stress accelerated sympathetic activity in the IBAT and heart more strongly than did nicotine loading alone. Pretreatment with nicotine suppressed the sympathetic activity induced by immobilization stress to the same extent as that observed after administering nicotine alone. Thus, these results appeared to support our hypothesis.

Survey of fluctuating fetal body weights in Sprague-Dawley rats

During the past 9 years of reproductive and developmental toxicity studies in Sprague-Dawley rat, we noticed that the average fetal body weight on day 20 of gestation in 81 control groups fluctuated significantly from study to study. The other parameters such as number of implants, resorption rats and number of live fetuses were relatively stable. With information cooperatively given by the animal supplier, we could pin down the possibility of the fluctuation. The animal supplier introduced Sprague-Dawley rats into Japan from the U. S. twice in the past. The documents we analyzed indicated that the fluctuation in fetal body weight was caused by different two colonies which were introduced into Japan at the different times.