• The Korean Journal of Physiology
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• v.16 no.2
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• pp.209-213
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• 1982

This study was conducted to investigate the effect of ingestion of sesame (Sesamum indicum) gruel as a nourishing meal upon the plasma gastrin concentration in normal Korean. Sixteen normal persons with no history of gastrointestinal diseases, including male and female were studied. After an overnight(about 15 hrs) fast, eight persons(mean age: 26.6, range: $20{\sim}40$ years) of them ingested a 350 ml sesame gruel corresponding to 12 g protein, 13 g fat and 99 g carbohydrate, and the remaining 8 subjects(mean age: 21.3, range: $20{\sim}24$ years) ingested a 350 ml glutinous rice gruel(control meal) corresponding to 8 g protein, 1 g fat and 115 g carbohydrate. The venous blood samples were drawn before and after the ingestion of the test meal for the measurement of gastrin by means of radioimmunoassay. 1) Plasma gastrin concentration in response to the ingestion of sesame gruel or glutinous rice gruel increased significantly compared with the concentration in fasting state. 2) Mean increment or percent increment in postprandial plasma gastrin concentration after the ingestion of sesame gruel was not significantly different from that after the control meal, i.e. the glutinous rice gruel. It is inferred from the above results that the ingestion of sesame contained in sesame gruel may have no significant influence on gastrin release in normal human subjects.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.6
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• pp.323-330
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• 2008

The properties of voltage dependent $Ca^{2+}$ current (VDCC) were investigated in interstitial cells of Cajal (ICC) distributed in the myenteric layer (ICC-MY) of guinea-pig antrum. In tissue, ICC-MY showed c-Kit positive reactions and produced driving potentials with the amplitude and frequency of about 62 mV and 2 times $min^{-1}$ respectively, in the presence of $1{\mu}M$ nifedipine. Single ICC-MY isolated by enzyme treatment also showed c-Kit immunohistochemical reactivity. These cells were also identified by generation of spontaneous inward current under $K^+$ -rich pipette solution. The voltage clamp experiments revealed the amplitude of - 329 pA inward current at irregular frequency. With $Cs^+$-rich pipette solution at $V_h=-80\;mV$, ICC-MY produced voltage-dependent inward currents (VDIC), and nifedipine ($1{\mu}M$) blocked VDIC. Therefore, we successfully isolated c-Kit positive single ICC from guinea-pig stomach, and found that ICC-MY potently produced dihydropiridine sensitive L-type voltage-dependent $Ca^{2+}$ currents ($VDCC_L$).

• Molecules and Cells
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• v.21 no.3
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• pp.337-342
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• 2006

Interstitial cells of Cajal (ICCs) are pacemaker cells that activate the periodic spontaneous depolarization (pacemaker potentials) responsible for the production of slow waves in gastrointestinal smooth muscle. The effects of vasoactive intestinal polypeptide (VIP) on the pacemaker potentials in cultured ICCs from murine small intestine were investigated by whole-cell patch-clamp techniques. Addition of VIP (50 nM-$1{\mu}M$) decreased the amplitude of pacemaker potentials and depolarized resting membrane potentials. To examine the type of receptors involved in ICC, we examined the effects of the $VIP_1$ agonist and found that it had no effect on pacemaker potentials. Pretreatment with $VIP_1$ antagonist ($1{\mu}M$) for 10 min also did not block the VIP (50 nM)-induced effects. On the other hand exposure to 1H-(1,2,4)oxadiazolo(4,3-A)quinoxalin-1-one (ODQ, $100{\mu}M$), an inhibitor of guanylate cyclase, prevented VIP inhibition of pacemaker potentials. Similarly KT-5823 ($1{\mu}M$) or RP-8-CPT-cGMPS ($10{\mu}M$), inhibitors of protein kinase G (PKG) blocked the effect of VIP (50 nM) on pacemaker potentials as did N-nitro-L-arginine (L-NA, $100{\mu}M$), a non-selective nitric oxide synthase (NOS) inhibitor. These results imply that the inhibition of pacemaker activity by VIP depends on the NO-cGMP-PKG pathway.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.4
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• pp.341-346
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• 2014

Lubiprostone is a chloride ($Cl^-$) channel activator derived from prostaglandin $E_1$ and used for managing constipation. In addition, lubiprostone affects the activity of gastrointestinal smooth muscles. Interstitial cells of Cajal (ICCs) are pacemaker cells that generate slow-wave activity in smooth muscles. We studied the effects of lubiprostone on the pacemaker potentials of colonic ICCs. We used the whole-cell patch-clamp technique to determine the pacemaker activity in cultured colonic ICCs obtained from mice. Lubiprostone hyperpolarized the membrane and inhibited the generation of pacemaker potentials. Prostanoid $EP_1$, $EP_2$, $EP_3$, and $EP_4$ antagonists (SC-19220, PF-04418948, 6-methoxypyridine-2-boronc acid N-phenyldiethanolamine ester, and GW627368, respectively) did not block the response to lubiprostone. L-NG-nitroarginine methyl ester (L-NAME, an inhibitor of nitric oxide synthase) and 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ, an inhibitor of guanylate cyclase) did not block the response to lubiprostone. In addition, tetraethylammonium (TEA, a voltage-dependent potassium [$K^+$] channel blocker) and apamin (a calcium [$Ca^{2+}$]-dependent $K^+$ channel blocker) did not block the response to lubiprostone. However, glibenclamide (an ATP-sensitive $K^+$ channel blocker) blocked the response to lubiprostone. Similar to lubiprostone, pinacidil (an opener of ATP-sensitive $K^+$ channel) hyperpolarized the membrane and inhibited the generation of pacemaker potentials, and these effects were inhibited by glibenclamide. These results suggest that lubiprostone can modulate the pacemaker potentials of colonic ICCs via activation of ATP-sensitive $K^+$ channel through a prostanoid EP receptor-independent mechanism.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.353-359
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• 1998

In gastrointestinal smooth muscle, muscarinic stimulation by carbachol (CCh) activates nonselective cation channel current ($I_{CCh}$) which is facilitated by intracellular [$Ca^{2+}$] increase. Caffeine is widely used in experiments to mobilize $Ca^{2+}$ from intracellular stores. This study shows a strong inhibitory effect of caffeine on $I_{CCh}$ in guinea-pig gastric myocyte. In this study, the underlying mechanism of the inhibitory effect of caffeine was investigated. $I_{CCh}$ was completely suppressed by the addition of caffeine (10 mM) to the superfusing solution. Inhibition of $I_{CCh}$ by caffeine was not related to the intracellular cAMP accumulation which was expected from the phosphodiesterase-inhibiting effect of caffeine. The blockade of $InsP_3-induced$ $Ca^{2+}$ release by heparin had no significant effects on the activation of $I_{CCh}$. When the same cationic current had been induced by intracellular dialysis of $GTP[{\gamma}S]$ in order to bypass the muscarinic receptor, the inhibitory effect of caffeine was significantly attenuated. The results of this study indicate that both intracellular signalling pathways for $I_{CCh}$, proximal and distal to G-protein activation, are suppressed by caffeine. A major inhibition was observed at the proximal level.

• International Journal of Oral Biology
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• v.43 no.3
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• pp.113-121
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• 2018

Taste is closely related to intake of food. Taste perception is also influenced by type of food ingested, and nutrition and health status. Bitter taste plays an important role in the survival of human and animals to avoid probable toxic and harmful substances. Vertebrate animals recognize bitter taste through type 2 taste receptors (T2Rs). Several T2Rs have been expressed extra-oral such as the gastrointestinal tract, respiratory tract, urogenital tract, brain and immune cells, and parts of their functions are being revealed. This review will discuss physiological roles of T2Rs in relation to innate immunity, secretion and smooth muscle contraction expressed in extra-oral cells and tissues, and we summarize relationships between polymorphisms in T2Rs and general or oral diseases. It is not a coincidence that animals pay much genetic costs for taste and smell during evolution.

• Journal of the korean veterinary medical association
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• v.37 no.8
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• pp.706-713
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• 2001

자연적인 서식지에서 토끼는 번번히 육식 동물의 먹이가 된다. 이들의 일차적이고 우선적인 생존 반응은 발견을 피하기 위한 노력으로 조용히 있는 것이다. 토끼는 폭발적인 속도를 빠르게 낼 수 있고 짧은 거리에서 즉시 방향을 바꿀 수 있도록 가벼운 뼈, 작은 앞다리, 강력하고 잘 발달된 뒷다리를 가졌을 뿐만 아니라, 예민한 청각과 즉각적인 후각을 발달시킴으로써 'fight or flight(적자생존)'로 적응해왔다. 이런 생존 반응은 욕구가 없어진 것으로 나타나는 대부분의 집토끼에도 여전히 존재하지만, 이런 토끼들은 장애에 대해 반응이 불완전하고 변화에 쉽게 스트레스를 받는다. 스트레스를 받은 동물은 일차적으로 anorexia와 용변의 빈도와 일관성에 변화를 유발하는 건강, 생식, 행동적인 문제에 더욱 민감하다.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.5
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• pp.383-390
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• 2014

Gastrointestinal motility consists of phasic slow-wave contractions and the migrating motor complex (MMC). Eupatilin (Stillen$^{(R)}$) has been widely used to treat gastritis and peptic ulcers, and various cytokines and neuropeptides are thought to be involved, which can affect gastrointestinal motility. We performed a study to identify the effects of eupatilin on lower gastrointestinal motility with electromechanical recordings of smooth muscles in the human ileum and colon. Ileum and colon samples were obtained from patients undergoing bowel resection. The tissues were immediately stored in oxygenated Krebs-Ringer's bicarbonate solution, and conventional microelectrode recordings from muscle cells and tension recordings from muscle strips and ileal or colonic segments were performed. Eupatilin was perfused into the tissue chamber, and changes in membrane potentials and contractions were measured. Hyperpolarization of resting membrane potential (RMP) was observed after administration of eupatilin. The amplitude, AUC, and frequency of tension recordings from circular and longitudinal smooth muscle strips and bowel segments of the ileum and colon were significantly decreased after admission of eupatilin. Eupatilin elicited dose-dependent decreases during segmental tension recordings. In conclusion, eupatilin (Stillen$^{(R)}$) showed inhibitory effects on the human ileum and colon. We propose that this drug may be useful for treating diseases that increase bowel motility, but further studies are necessary.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1199-1206
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• 2004

This study was examined the effects of Daesenggi-Tang on intestinal mucosa and gastrointestinal transit time and plasma lipids in rats. Adult male rats were fed four weeks on diets containing no addition(basal diet group), 5% cellulose(cellulose group) and Daesenggi-Tang group(Daesenggi-Tang group). The results were as follows; 1. The gastrointestinal transit times was significantly decreased in Daesenggi-Tang administered group compare to basal diet and cellulose groups. Carmine red mixed with Daesenggi-Tang, as a marker, was administered through a gastric tube for stomach or intracecally by a chronically implanted catheter for colon transit. Small intestinal transit and large intestinal transit time were significantly decreased in Daesenggi-Tang administered group compare to basal diet. 3. The height of jejunal villi was developed in Daesenggi-Tang administered group compare to basal diet. The thickness of mucosa and muscle layer of colonic mucosa were significantly developed in Daesenggi-Tang administered group compare to basal diet group. 4. The numerical change of goblet cell in colonic mucosa was increased acid mucin stained alcian blue in Daesenggi-Tang administered group compare to basal diet and cellulose group. 6. HDL-cholesterol of plasma lipid was increased in Daesenggi-Tang administered group compare to basal diet and cellulose groups. Theses results suggests that Daesenggi-Tang may be used in prevention and treatment of constipation resulting in increase of fecal weight, decrease of gastrointestinal transit time, development of intestinal villi, intensify of stainability of acid mucin in colon.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.987-992
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• 2008

This study was carried out to understand the macroscopic aspects of the digestive system symptoms occurring after taking oriental herb complex decoction as observing morphological changes in esophagus, stomach and duodenal bulb by endoscopy of upper gastrointestinal tract when these symptoms developed. The subjects of this study were 46 patients (male 22, female 24, mean age : $54.72{\pm}14.26$ years) who were chosen among ones who took oriental herb complex decoction for medical care and developed symptoms related to the gastrointestinal tract while taking an oriental herb decoction, which were assumed that the digestive symptoms were newly developed because of administration. The subjects were given morphological examination by endoscopy of the upper gastrointestinal tract. As a result of the endoscopy operated due to the digestive symptoms developed during the administration of oriental herb decoction, there were 2 cases of esophagitis, 5 cases of acute gastritis, 1 case of chronic gastritis A type, 15 cases of chronic gastritis B type, 1 case of duodenitis, 1 case of gastric ulcer, 1 case of gastric polyp, 2 cases of intestinal metaplasia, 1 case of gastric ptosis and 17 cases of normal findings which didn't have any abnormality macroscopically with endoscopy. With regards to the patients who complained of the digestive symptoms after taking oriental herb decoction, it has been found that the symptoms occurred as the oriental herbal medicine taken by the patients who had the digestive symptoms at ordinary times influenced on the gastrointestinal tract. Especially, many of them were had chronic gastritis and functional dyspepsia in the past. The disease accompanying macroscopic lesions at endoscopy which occurred due to the oriental herb decoction as direct cause, was acute gastritis, and it was the prescription to cure the pains and inflammations of skeletomuscular disease.