Iron Contents in Rice Food Derived from the Iron Pot, and In Vitro Study Regarding Heme Oxygenase-1 Activity / 임상소아혈액종양

BACKGROUND: Iron pots have long been used for cooking in several countries. Early studies have shown that the use of such iron pots can increase the iron content of food cooked in them and that this increased iron content has some effect on iron uptake. This study was designed to evaluate the iron content in rice cooked in a traditional iron pot and study the iron uptake by macrophages through heme oxygenase-1 (HO-1). METHODS: The iron pot used in this study was round-shaped and had no legs. The iron content of rice cooked in the iron pot was measured. Thereafter, the bioavailability of iron was measured using western blot analysis. RESULTS: A total of 35 samples were analyzed for iron concentrations, which were 10.94±18.08 mg/L (range: 0.18–56.53 mg/L). The biochemical activity in most of materials was 1.5–9 times that of the activity observed in the control group. CONCLUSION: The iron concentration of rice cooked in iron pots were found to be relatively high. The introduction of iron pots in routine cooking practices may be a promising way of increasing the supply of iron, especially for people with severe iron deficiency anemia. Further, increased activity of HO-1, induced by supplementation of iron from the cast iron, may help in maintaining iron homeostasis.

Iron Contents in Rice Food Derived from the Iron Pot, and In Vitro Study Regarding Heme Oxygenase-1 Activity / 임상소아혈액종양

BACKGROUND: Iron pots have long been used for cooking in several countries. Early studies have shown that the use of such iron pots can increase the iron content of food cooked in them and that this increased iron content has some effect on iron uptake. This study was designed to evaluate the iron content in rice cooked in a traditional iron pot and study the iron uptake by macrophages through heme oxygenase-1 (HO-1).METHODS: The iron pot used in this study was round-shaped and had no legs. The iron content of rice cooked in the iron pot was measured. Thereafter, the bioavailability of iron was measured using western blot analysis.RESULTS: A total of 35 samples were analyzed for iron concentrations, which were 10.94±18.08 mg/L (range: 0.18–56.53 mg/L). The biochemical activity in most of materials was 1.5–9 times that of the activity observed in the control group.CONCLUSION: The iron concentration of rice cooked in iron pots were found to be relatively high. The introduction of iron pots in routine cooking practices may be a promising way of increasing the supply of iron, especially for people with severe iron deficiency anemia. Further, increased activity of HO-1, induced by supplementation of iron from the cast iron, may help in maintaining iron homeostasis.

The relaxing effect of Poncirus fructus and its flavonoid content on porcine coronary artery / 한국실험동물학회지

Coronary artery disease is a common occurrence in human, and causes enormous social cost. Poncirus fructus (PF), the dried immature fruits of Poncirus trifoliata Rafinesquem, is used in the treatment of womb contraction and dyspepsia, as a prokinetic, and in improving blood circulation. This study was performed to investigate the effects of PF and some of its flavonoids components on the coronary from the pig. The arterial ring was suspended by a pair of stainless steel stirrups in an organ bath. The end of the upper stirrup was connected to an isometric force transducer. A dose-dependent induction of relaxation was observed by both water and 70% ethanol extracts of PF in the porcine coronary artery precontracted with U46619 (100 nM), a stable analogue of the potent vasoconstrictor thromboxane A2. The 70% ethanol extract showed more efficacy than the water extract. Pretreatment of the artery with L-NAME (100 microM), a nitric oxide synthase inhibitor, resulted in a significant reduction in the relaxation induced by PF extract. In addition, ODQ (10 microM), a soluble guanylate cyclase inhibitor, also significantly reduced the effects of PF extracts. Hesperidin, a flavonoid present in PF, induced very weak relaxation of the porcine coronary artery at a high concentration (100 microM), while its aglycone, hesperetin, demonstrated a dose-dependent relaxation. In conclusion, PF extracts induced relaxation in the porcine coronary artery, partially through the nitric oxide-cGMP pathway, and the aglycones of flavonoids might be also involved in the relaxation of the same artery.

Alterations of Colonic Contractility in an Interleukin-10 Knockout Mouse Model of Inflammatory Bowel Disease

BACKGROUND/AIMS: Inflammatory bowel disease is commonly accompanied by colonic dysmotility and causes changes in intestinal smooth muscle contractility. In this study, colonic smooth muscle contractility in a chronic inflammatory condition was investigated using smooth muscle tissues prepared from interleukin-10 knockout (IL-10(-/-)) mice. METHODS: Prepared smooth muscle sections were placed in an organ bath system. Cholinergic and nitrergic neuronal responses were observed using carbachol and electrical field stimulation with L-NG-nitroarginine methyl ester (L-NAME). The expression of interstitial cells of Cajal (ICC) networks, muscarinic receptors, neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) was observed via immunofluorescent staining. RESULTS: The spontaneous contractility and expression of ICC networks in the proximal and distal colon was significantly decreased in IL-10(-/-) mice compared to IL-10(+/+) mice. The contractility in response to carbachol was significantly decreased in the proximal colon of IL-10(-/-) mice compared to IL-10(+/+) mice, but no significant difference was found in the distal colon. In addition, the expression of muscarinic receptor type 2 was reduced in the proximal colon of IL-10(-/-) mice. The nictric oxide-mediated relaxation after electrical field stimulation was significantly decreased in the proximal and distal colon of IL-10(-/-) mice. In inflamed colon, the expression of nNOS decreased, whereas the expression of iNOS increased. CONCLUSIONS: These results suggest that damage to the ICC network and NOS system in the proximal and distal colon, as well as damage to the smooth muscle cholinergic receptor in the proximal colon may play an important role in the dysmotility of the inflamed colon.

Inhibitory effect of Suaeda asparagoides (Miq.) extract on the motility of rat gastric antrum is mediated by beta-adrenoceptor / 한국실험동물학회지

Suaeda asparagoides (Miq.) has long been used as a Korean folk herbal medicine for the treatment of functional gastrointestinal disorders. However, reports on its pharmacological activity on gastrointestinal motility are scarce. The present study investigated the effects of Suaeda asparagoides water fraction of the extract (SAWF) on antral motility in vitro. Muscle strips from rat gastric antrum were set up in an organ bath in a circular orientation. SAWF (100 microg/mL) inhibited the spontaneous contraction of antral circular muscle strips. These inhibitory effects were not significantly affected by tetrodotoxin (1 microM), N omega-Nitro-L-arginine methyl ester hydrochloride (100 microM), 1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one (10 microM), ryanodine (10 microM) and phentolamine (10 microM). SAWF-induced inhibition was mostly restored by cyclopiazonic acid (10 microM). Furthermore, the beta-adrenergic receptor antagonist, propranolol (10 microM), abolished SAWF-induced inhibition. These results suggest that SAWF may exert its activity on gastrointestinal smooth muscle via a-adrenergic receptors and sarcoplasmic reticulum Ca2+ ATPase.

Alterations of Colonic Contractility in Long-term Diabetic Rat Model

BACKGROUND/AIMS: Dysfunction of the gastrointestinal tract occurs in about 76% of patients who are diabetic for more than 10 years. Although diabetes-related dysfunctions of the stomach such as gastroparesis have been extensively studied over the recent years, studies about the mechanism underlying colonic symptoms in long-term diabetes models are rare. Therefore, the goal of our study was to clarify the nature of colonic dysfunction in a long-term diabetic rat model. METHODS: The characteristics of colonic smooth muscle were investigated in Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an animal model of type 2 diabetes. These results were compared to those obtained from Long-Evans Tokushima Otsuka (LETO) control rats. RESULTS: Spontaneous contractility of the proximal colon was significantly decreased in the diabetic rats compared to the controls, while the spontaneous contractility of the distal colon was not. The number of interstitial cells of Cajal networks in the proximal colon was greatly decreased in diabetic rats compared to the controls. Contractility of the proximal colon in response to carbachol, an acetylcholine receptor agonist, was significantly weaker in the diabetic rats. In addition, the degree of relaxation in response to nitric oxide in the proximal colon of diabetic rats also appeared to be attenuated. CONCLUSIONS: The results from our study suggest that the decrease of interstitial cells of Cajal network, cholinergic receptors, and neuronal nitric oxide synthase in the proximal colon plays important roles in diabetes-related dysfunction of colon.

Electroacupuncture ameliorates experimental colitis induced by acetic acid in rat

The effect of electroacupuncture (EA) on experimental colitis was investigated in Sprague-Dawley rats. Colitis was induced by intracolonic instillation of 4% acetic acid. EA (2 Hz, 0.05 ms, 2 V for 20min) was applied to bilateral Hoku (LI-4) and Zusanli (ST-36) on 12 hrs and 36 hrs after induction of colitis. EA-treatment significantly reduced the macroscopic damage and the myeloperoxidase activity of colonic samples at 3 days post-induction of colitis. Colitic colon showed a decreased in vitro motility. However, colonic motility of EAtreated group was not significantly different from that of normal group. The anti-inflammatory effect of EA was not inhibited by a glucocorticoid receptor antagonist, RU-486, but suppressed by a beta-adrenoceptor antagonist, propranonol. These results suggest that EA-treatment has a beneficial effect on colitis, and its anti-inflammatory effect is mediated by beta-adrenoceptor activation but not by endogenous glucocorticoiddependent mechanism.

Rocuronium Onset at the Adductor Pollicis and Masseter Muscles for Endotracheal Intubation in Children / 대한마취과학회지

BACKGROUND: Masseter muscle is a better predictor of good intubating conditions than adductor pollicis after the administration of rocuronium in adults. We compared the onset of rocuronium at the masseter muscle to that at the adductor pollicis to determine which is the more suitable predictor of good intubating conditions using rocuronium in children. METHODS: Fifty children aged from 1 to 6 years old, were anesthetized with thiopental sodium and sevoflurane. The ulnar nerve was stimulated to monitor the relaxation of the adductor pollicis, and the mandibular nerve for monitoring masseter muscle relaxation. Rocuronium 0.6 mg/kg was administered. We measured the time to maximal blckade of the masseter muscle (M-0%). We recorded the percentage of relaxation of the adductor pollicis (AP-%) at M-0% and the time of the maximal blockade of the adductor pollicis (AP-0%), from the administration of rocuronium. Endotracheal intubation was started when the masseter muscle contraction was maximally blocked. RESULTS: M-0% occurred at 37.4 +/- 15.4 s, and AP-% was 32.4 +/- 32.2% at M-0%. AP-0% occurred at 54.8 +/- 19.0 s. The time gap between M-0% and AP-0% was 16.8 +/- 18.3 s. Intubation was at 64.4 +/- 19.4 s from the administration of rocuronium. CONCLUSIONS: The time gap between M-0% and AP-0% was very short in children. Therefore, the monitoring of muscle relaxation on masseter muscle is not straightforward, and therefore, not advised.

Inwardly Rectifying K+ Currents in Gastric Myocytes of Guinea-pig

To identify the presence of inwardly rectifying K+ channels and its characteristics, membrane currents were measured using a whole-cell patch clamp from isolated gastric myocytes of guinea-pig. Change of external K+ concentration from 5 to 90 mM induced an inward current at a holding potential of 80 mV. The high K+-induced inward current was blocked by Ba2+ and Cs+, but not by glibenclamide. With 90 mM K+ in bath, the Ba2+- and Cs+-sensitive currents showed strong inward rectification. Ten mM TEA weakly blocked the inward current only at potentials more negative than 50 mV. With 90 mM K+ in bath, hyperpolarizing step pulses from 10 mV induced inward currents, which were inactivated at potentials more negative than 70 mV. Reduction of external K+ to 60 mM decreased the amplitudes of the currents and shifted the reversal potential to more negative potential. The inactivation of inward K+ current at negative clamp voltage was not affected by removing external Na . These results suggest that the inwardly rectifying K+ channels may exist in gastric smooth muscle.