Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage (31.0%+/-8.09% in P4 group to 65.5%+/-24.08% in P2 group), compared with that obtained in the abscence of Ara-C (17.6%+/-6.03%) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to 56.22%+/-0.67% and GFAP positive cells to 66.46%+/-1.83% in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.
Adult ; Animals ; Cell Count ; Cell Culture Techniques ; Cytarabine* ; Fibroblasts ; Ganglia, Spinal* ; Humans ; Neurons ; Peripheral Nervous System ; Rats* ; Schwann Cells ; Spinal Nerve Roots*

In this study, we examined if glucocorticoids are required for the fasting-induced decrease of neuronal nitric oxide synthase (nNOS) in the magnocellular division of the paraventricular nucleus (PVN). Rats were adrenalectomized, subjected to 48 h of food deprivation with/without dexamethasone (5 mg/ kg, 4 subcutaneous injections with 12 h intervals), and the brain slices were processed for NADPH-diaphorase (NADPH- d) staining, a histochemical marker for nNOS in neuronal cells. In food deprived adrenalectomized rats, but not in free fed intact rats, dexamethasone significantly decreased NADPH-d staining in the magnocellular PVN. We previously reported that food deprivation decreases nNOS in the magnocellular PVN of intact rats. Thus, the present results together with our previous report suggest that although glucocorticoids are required for fasting-induced nNOS down-regulation in the magnocellular PVN, glucocorticoids may not be directly involved and some other molecular signals produced by food deprivation may play a pivotal role over glucocorticoid in the regulatory pathway for nNOS expression in this brain region.
Adrenalectomy ; Animals ; Dexamethasone/pharmacology ; Down-Regulation ; Fasting/*metabolism ; Male ; NADPH Dehydrogenase/*analysis ; Nitric-Oxide Synthase/genetics ; Paraventricular Hypothalamic Nucleus/*enzymology ; Peptides/physiology ; Rats ; Rats, Sprague-Dawley ; Research Support, Non-U.S. Gov't ; Weight Gain

This study was conducted to define the underlying mechanism of hypophagia induced by increased central serotonergic action. Rats received 3 daily injections of 5-hydroxy-L-tryptophan (5-HTP), a serotonin precursor, at a dose of 100 mg/kg/10 ml saline at 1 h before lights off. A significant suppression in food intake was observed shortly after the 5-HTP injection and persisted during 3 daily 5-HTP injections. Neuropeptide Y (NPY) expression in the arcuate nucleus increased after 3 days of 5-HTP treatment, as high as in the pair-fed group. Immunoreactivity of phosphorylated extracellular signal-regulated protein kinase (pERK1/2) in the hypothalamic paraventricular nucleus (PVN) was increased markedly by 3 days of 5-HTP treatment, but not by 3 days of pair-fed. mRNA expression levels of serotonin reuptake transporter (5-HTT) was increased in the dorsal raphe nucleus of the 5-HTP treated rats, but not in the pair-fed group. Results suggest that increased pERK1/2 in the PVN of 5-HTP injected rats may be a part of serotonergic anorectic signaling, perhaps blunting the orectic action of NPY; i.e., 5-HTP injected rats showed hypophagia despite of increased NPY expression in the arcuate nucleus.
5-Hydroxytryptophan ; Animals ; Arcuate Nucleus ; Eating ; Hypothalamus ; Light ; Neuropeptide Y ; Paraventricular Hypothalamic Nucleus ; Protein Kinases ; Raphe Nuclei ; Rats ; RNA, Messenger ; Serotonin

BACKGROUND: This study was conducted to examine the effects of ad libitum consumption of highly palatable food (HPF) during adolescence on the adverse behavioral outcome of neonatal maternal separation. METHODS: Male Sprague-Dawley pups were separated from dam for 3 hours daily during the first 2 weeks of birth (maternal separation, MS) or left undisturbed (nonhandled, NH). Half of MS pups received free access to chocolate cookies in addition to ad libitum chow from postnatal day 28 (MS+HPF). Pups were subjected to behavioral tests during young adulthood. The plasma corticosterone response to stress challenge was analyzed by radioimmunoassay. RESULTS: Daily caloric intake and body weight gain did not differ among the experimental groups. Ambulatory activities were decreased defecation activity and rostral grooming were increased in MS controls (fed with chow only) compared with NH rats. MS controls spent less time in open arms, and more time in closed arms during the elevated plus maze test, than NH rats. Immobility duration during the forced swim test was increased in MS controls compared with NH rats. Cookie access normalized the behavioral scores of ambulatory and defecation activities and grooming, but not the scores during the elevated plus maze and swim tests in MS rats. Stress-induced corticosterone increase was blunted in MS rats fed with chow only, and cookie access normalized it. CONCLUSION: Prolonged access to HPF during adolescence and youth partly improves anxiety-related, but not depressive, symptoms in rats that experienced neonatal maternal separation, possibly in relation with improved function of the hypothalamic-pituitary-adrenal (HPA) axis.
Adolescent* ; Animals ; Anxiety ; Arm ; Axis, Cervical Vertebra* ; Body Weight ; Cacao ; Corticosterone ; Defecation ; Depression ; Divorce ; Energy Intake ; Grooming ; Humans ; Male ; Parturition ; Plasma ; Radioimmunoassay ; Rats* ; Rats, Sprague-Dawley

LiCl at doses sufficient to induce conditioned taste aversion (CTA) causes c-Fos expression in the brain regions implicated in CTA formation. It has been reported that nitric oxide (NO) may play a role in CTA learning and LiCl increases both the synthesis and activity of NO synthase (NOS) in the brain. In this study, we examined the effect of central N omega-nitro-L- arginine methyl ester (L-NAME) on the brain c-Fos expression and CTA learning induced by lithium in rats. In the results, intracerebroventricular L-NAME given prior to lithium did not change either the lithium-induced CTA or c-Fos in the relevant brain regions. This suggests that the brain NO system may not be involved in the neuronal activation during lithium-induced CTA formation.
Animals ; Avoidance Learning/*drug effects/physiology ; Brain/*physiology ; Conditioning (Psychology) /*drug effects/physiology ; Immunohistochemistry ; Injections, Intraventricular ; Lithium/*pharmacology ; Male ; NG-Nitroarginine Methyl Ester/*pharmacology ; Nitric Oxide/physiology ; Proto-Oncogene Proteins c-fos/*analysis ; Rats ; Rats, Sprague-Dawley ; Support, Non-U.S. Gov't ; Taste/*drug effects/physiology

Axotomy of the vagal motor neurons by cervical vagotomy induces NADPH diaphorase staining due to increased nitric oxide synthase expression in both the rat dorsal motor nucleus and nucleus ambiguous; furthermore, cerical vagotomy leads to cell death of the dorsal motor nucleus cells. Subdiaphragmatic vagotomy axotomizes the vagal motor cells further from the brainstem than cervical vagotomy, and cuts the fibers running only to the abdominal viscera. Here we report that subdiaphragmatic vagotomy is sufficient to induce NADPH diaphorase staining in the dorsal motor nucleus but does not induce staining in the nucleus ambiguus. Because the neurons of the dorsal motor nucleus do not undergo cell death after subdiaphragmatic vagotomy and are able to re-enervate the gut, the increased nitric oxide synthase expression after distal axotomy may be related more to regeneration than degeneration.
Animal ; Fourth Ventricle/physiology* ; Fourth Ventricle/enzymology* ; Fourth Ventricle/cytology ; Male ; Motor Neurons/enzymology ; NADPH Dehydrogenase/metabolism* ; Rats ; Rats, Sprague-Dawley ; Vagotomy/methods* ; Vagus Nerve/physiology*

INTRODUCTION: This study examined the regulatory mechanism underlying the meal-induced changes in the hypothalamic-pituitary-adrenal gland (HPA) axis activity. MATERIALS AND METHODS: Male Sprague-Dawley rats (250-300 g) were hired for two different experiments as follows; 1) rats received either 8% sucrose or 0.2% saccharin ad libitum after 48 h of food deprivation with the gastric fistula closed (real feeding) or opened (sham feeding). 2). rats received 5 ml of intra-oral infusion with 0.2% saccharin or distilled water after 48 h of food deprivation. One hour after food access, all rats were sacrificed by a transcardiac perfusion with 4% paraformaldehyde. The brains were processed for c-Fos immunohistochemistry and the cardiac blood was collected for the plasma corticosterone assay. RESULTS: Real feedings with sucrose or saccharin and sham feeding saccharin but not sucrose, following food deprivation decreased the plasma corticosterone level. c-Fos expression in the nucleus tractus of solitarius (NTS) of the fasted rats was increased by the consumption of sucrose but not saccharin, regardless of the feeding method. On the other hand, the consumption of sucrose or saccharin with real feeding but not the sham, induced c-Fos expression in the paraventricular nucleus (PVN) of the fasted rats. The intra-oral infusion with saccharin or water decreased the plasma corticosterone level of the fasted rats. Intra-oral water infusion increased c-Fos expression in both the PVN and NTS, but saccharin only in the NTS in the fasted rats. CONCLUSION: Neither restoration of the fasting-induced elevation of plasma corticosterone nor the activation of neurons in the PVN and NTS after refeeding requires the palatability of food or the post-ingestive satiety and caloric load. In addition, neuronal activation in the hypothalamic PVN may not be an implication in the restoration of the fasting-induced elevation of the plasma corticosterone by oropharyngeal stimuli of palatable food.
Animals ; Axis, Cervical Vertebra ; Brain ; Corticosterone ; Feeding Methods ; Food Deprivation ; Formaldehyde ; Gastric Fistula ; Hand ; Humans ; Immunohistochemistry ; Male ; Neurons ; Paraventricular Hypothalamic Nucleus ; Perfusion ; Plasma ; Polymers ; Rats ; Rats, Sprague-Dawley ; Saccharin ; Salicylamides ; Solitary Nucleus ; Sucrose ; Water

BACKGROUND: Dry eye is a common disease, and coffee is a popular beverage that is heavily consumed in Korea and worldwide. We examined the correlation between coffee consumption and dry eye.METHODS: This study was performed using data from the 5th Korean National Health and Nutrition Examination Survey, which was a cross-sectional study of the Korean population conducted from 24 months. We included adults aged ≥19 years who underwent ophthalmologic examination and excluded those who had comorbid conditions with dry eye. The subjects were divided into dry eye and control groups. The dry eye group consisted of those who had been clinically diagnosed with dry eye. A multiple logistic regression analysis was conducted to determine the correlation between coffee consumption and dry eye.RESULTS: An inverse correlation was found between coffee consumption and dry eye in the group that consumed 3 cups of coffee a day (P=0.001). However, after multivariate adjustment, the statistical significance of the correlation disappeared (P=0.283).CONCLUSION: Consumption of 3 cups of coffee a day in comparison to non-consumption group was negatively correlated with dry eye in an univariate analysis model, but the correlation was not statistically significant after adjusting for age, sex, body mass index, smoking, binge drinking, sun exposure time and history of eye surgery.
Adult ; Beverages ; Binge Drinking ; Body Mass Index ; Coffee ; Cross-Sectional Studies ; Dry Eye Syndromes ; Humans ; Korea ; Logistic Models ; Nutrition Surveys ; Smoke ; Smoking ; Solar System

Background: Coffee is the most commonly consumed beverage worldwide and has a variety of health benefits. However, the relationship between coffee consumption and bone mineral density (BMD) is still controversial. This study aimed to assess the associations between coffee consumption and BMD in Korean men aged 50 years and older. Methods: The study included 271 Korean men aged 50 years and older from the Fourth Korea National Health and Nutrition Examination Survey 2011. Coffee consumption frequency was assessed using a questionnaire and categorized as follows: none, ≤1 cup/day, 2 cups/day, or 3 cups/day. The BMD of the total femur, femur neck, and lumbar spine were compared based on coffee consumption frequency. Multiple logistic regression analysis was used to analyze the association between coffee consumption and impaired bone health (osteopenia or osteoporosis). Results: The BMD of the total femur and femur neck significantly increased with higher coffee consumption (P<0.001). Participants with the highest coffee consumption had the lowest odds ratio for osteopenia or osteoporosis of the total femur and femur neck (P<0.001 and P<0.05, respectively). After adjusting for all confounding factors, this trend remained consistent in the femur neck (P<0.05); drinking 2 cups of coffee per day was found to be associated with the lowest risk of osteopenia or osteoporosis of the total femur. Conclusion Coffee consumption was found to decrease the risk of osteopenia or osteoporosis of the total femur and femur neck in Korean men aged 50 years and older.

Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage (31.0%+/-8.09% in P4 group to 65.5%+/-24.08% in P2 group), compared with that obtained in the abscence of Ara-C (17.6%+/-6.03%) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to 56.22%+/-0.67% and GFAP positive cells to 66.46%+/-1.83% in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.
Adult ; Animals ; Cell Count ; Cell Culture Techniques ; Cytarabine* ; Fibroblasts ; Ganglia, Spinal* ; Humans ; Neurons ; Peripheral Nervous System ; Rats* ; Schwann Cells ; Spinal Nerve Roots*