• 대한동의생리학회:학술대회논문집
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• 2004.07a
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• pp.12-12
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• 2004

• Journal of Yeungnam Medical Science
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• v.40 no.1
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• pp.4-11
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• 2023

Caloric restriction is a popular approach to treat obesity and its associated chronic illnesses but is difficult to maintain for a long time. Intermittent fasting is an alternative and easily applicable dietary intervention for caloric restriction. Moreover, intermittent fasting has beneficial effects equivalent to those of caloric restriction in terms of body weight control, improvements in glucose homeostasis and lipid profiles, and anti-inflammatory effects. In this review, the beneficial effects of intermittent fasting are discussed.

• Proceedings of the Ginseng society Conference
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• 2007.12a
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• pp.69-69
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• 2007

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.3
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• pp.361-368
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• 1998

The spontaneous contractions of gastric smooth muscles are regulated by slow waves, which are modulated by both nervous system and humoral agents. This study was designed to examine the effects of prostaglandin $E_2$ ($PGE_2$) on the contractile and electrical activities of antral smooth muscles in guinea-pig stomach, using an intracellular recording technique. To elucidate the underlying mechanism for its effect on contractility, ionic currents were also measured using a whole-cell patch clamp method. The basal tone by $PGE_2$ was variable, whereas the magnitude of phasic contractions was reduced ($19.0{\pm}2.1%$, n=19). The resting membrane potentials were hyperpolarized ($-4.4{\pm}0.5%$ mV, n=10), and plateau potentials were lowered ($-2.9{\pm}0.5%$ mV, n=10). In most cases, however, the initial peak potentials of slow waves were depolarized more by $PGE_2$ than those of control. The frequency of the slows wave was increased from $5.7{\pm}0.2$ cycles/min to $6.5{\pm}0.2$ (n=22). Voltage-operated $Ca^{2+}$ currents were decreased by $PGE_2$ (n=5). Voltage-operated $K^+$ currents, both Ca-dependent and Ca-independent, were increased (n=5). These results suggest that $PGE_2$ plays an important role in the modulation of gastric smooth muscle activities, and its inhibitory effects on the contractility and activities of slow waves are resulted from both decrease of $Ca^{2+}$ currents and increase of $K^+$ currents.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.4
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• pp.255-262
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• 2022

Oxytocin is a neuropeptide produced primarily in the hypothalamus and plays an important role in the regulation of mammalian birth and lactation. It has been shown that oxytocin has important cardiovascular protective effects. Here we investigated the effects of oxytocin on vascular reactivity and underlying the mechanisms in human umbilical vein endothelial cells (HUVECs) in vitro and in rat aorta ex vivo. Oxytocin increased phospho-eNOS (Ser 1177) and phospho-Akt (Ser 473) expression in HUVECs in vitro and the aorta of rat ex vivo. Wortmannin, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K), inhibited oxytocin-induced Akt and eNOS phosphorylation. In the rat aortic rings, oxytocin induced a biphasic vascular reactivity: oxytocin at low dose (10^-9-10^-8 M) initiated a vasorelaxation followed by a vasoconstriction at high dose (10^-7 M). L-NAME (a nitric oxide synthase inhibitor), endothelium removal or wortmannin abolished oxytocin-induced vasorelaxation, and slightly enhanced oxytocin-induced vasoconstriction. Atosiban, an oxytocin/vasopressin 1a receptor inhibitor, totally blocked oxytocin-induced relaxation and vasoconstriction. PD98059 (ERK1/2 inhibitor) partially inhibited oxytocin-induced vasoconstriction. Oxytocin also increased aortic phospho-ERK1/2 expression, which was reduced by either atosiban or PD98059, suggesting that oxytocin-induced vasoconstriction was partially mediated by oxytocin/V1aR activation of ERK1/2. The present study demonstrates that oxytocin can activate different signaling pathways to cause vasorelaxation or vasoconstriction. Oxytocin stimulation of PI3K/eNOS-derived nitric oxide may participate in maintenance of cardiovascular homeostasis, and different vascular reactivities to low or high dose of oxytocin suggest that oxytocin may have different regulatory effects on vascular tone under physiological or pathophysiological conditions.

• The Korean Journal of Pain
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• v.35 no.3
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• pp.271-279
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• 2022

Background: Inflammation is known to underlie the pathogenesis in neuropathic pain. This study investigated the anti-inflammatory and neuroprotective mechanisms involved in antinociceptive effects of co-administration of acetaminophen and L-carnosine in chronic constriction injury (CCI)-induced peripheral neuropathy in male Wistar rats. Methods: Fifty-six male Wistar rats were randomly divided into seven experimental groups (n = 8) treated with normal saline/acetaminophen/acetaminophen + L-carnosine. CCI was used to induce neuropathic pain in rats. Hyperalgesia and allodynia were assessed using hotplate and von Frey tests, respectively. Investigation of spinal proinflammatory cytokines and antioxidant system were carried out after twenty-one days of treatment. Results: The results showed that the co-administration of acetaminophen and L-carnosine significantly (P < 0.001) increased the paw withdrawal threshold to thermal and mechanical stimuli in ligated rats compared to the ligated naïve group. There was a significant (P < 0.001) decrease in the levels of nuclear factor kappa light chain enhancer B cell inhibitor, calcium ion, interleukin-1-beta, and tumour necrotic factor-alpha in the spinal cord of the group coadministered with acetaminophen and L-carnosine compared to the ligated control group. Co-administration with acetaminophen and L-carnosine increased the antioxidant enzymatic activities and reduced the lipid peroxidation in the spinal cord. Conclusions: Co-administration of acetaminophen and L-carnosine has anti-inflammatory effects as a mechanism that mediate its antinociceptive effects in CCI-induced peripheral neuropathy in Wistar rat.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.169-177
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• 1987

The effects of higenamine were investigated in the single atrial and ventricular myocyte of the guinea pig by using patch clamp method. The results obtained were as follows: 1) Isoprenaline which is known to be ${\beta}-agonist$ increased the duration of action potential and calcium current in ventricular cells. 2) Higenamine also increased the duration of action potential and calcium current in ventricular myocytes. And its effect was blocked by propranolol. 3) In the atrial cells, isoprenaline showed ${\beta}-agonist$ effects, which were increasing the duration of action potential and calcium current same as in ventricular cells. 4) Higenamine, however, showed the opposite effects of ${\beta}-agonist$ which were decreasing the duration of action potential and calcium current. The above results suggest that higenamine has the typical ${\beta}-agonist$ effect in ventricular cells but inhibitory effect in atrial cells and this effect on atrium could be due to the reduction of calcium current.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.11a
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• pp.190-192
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• 2009

Kainic acid (KA), an agonist for kainate and AMPA receptors, is an excitatory neurotoxic substance. Vitamin E such as alpha-tocopherol and alpha-tocotrienol is a chain-breaking antioxidant, preventing the chain propagation step during lipid peroxidation. In the present study, we have investigated the neuroprotective effects of alphatocopherol and alpha-tocotrienol on KA-induced neuronal death using organotypic hippocampal slice culture (OHSC). After 15h KA treatment, delayed neuronal death was detected in CA3 region. Alpha-tocopherol and alpha-tocotrienol increased cell survival and reduced the number of TUNEL-positive cells in CA3 region. These data suggest that alpha-tocopherol and alpha-tocotrienol treatment have protective effects on KA-induced cell death

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.2
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• pp.91-97
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• 1989

The present experiment was carried out to investigate the effects of heat exposure on water metabolism and the passage of indigestible particles in sheep. Water intake, respiratory rate, rectal temperature and pH of ruminal fluid and urine were significantly higher (P<0.05) in the hot environment ($32\;^{\circ}C$) than in the control environment ($20\;^{\circ}C$). Urine osmolality and blood volume were increased, while glomerular filtration rate was decreased, in the hot environment. The liquid flow rate from reticulo-rumen and the excretion of indigestible particles of specific gravity 0.99 (but not 1.27 or 1.38) were increased in the hot environment. From these findings, it is suggested that an increased water intake evoked by heat exposure might affect the flow rate of digesta in sheep.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.549-552
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• 2003

To investigate the protective effect of Sophorae Radix (SR) on the damage by pulmonary vascular endothelial cells by xanthine oxidase (XO)/hypoxanthine (HX)-induced oxygen tree radical, Neutral Red (NR) and c-fos immunopositive cell assay were used. The results were obtained as follows ; The viability of vascular endothelial cells treated with XO/HX was decreased. And c-fos immunopositive cells represented a maximal increase in group treated with XO/HX for 2 hour in pulmonary vasvular endothelial cells. But pretreated groups with SR extracts were not inhibited the increase of c-fos immunopositive cells by XO/HX in a dose-dependent manner. These results show that XO/HX elicits toxic effects in cultured pulmonary vascular endothelial cells, and suggest that SR extract is very effective in the prevention of XO/HX-induced increase of c-fos immunopositive cells.