• Proceedings of the Ginseng society Conference
• /
• 2005.11a
• /
• pp.41-63
• /
• 2005

Ginseng has been useful for the treatment of diverse disease in oriental countries for thousands of years. In addition, a folk medicine prescribed by seven herbal drugs including Panax ginseng has been antinarcotics in the treatment of morphine-dependent patients. Many articles have been reported on these works. Therefore, we review the protective effects of Panax ginseng on the neurotoxicity induced by abuse drugs. Ginseng total saponins (GTS) extracted and isolated by Panax ginseng antagonized morphine-induced analgesia, and inhibited the development of analgesic tolerance to and physical dependence on morphine. CTS inhibited morphine-6 dehydrogenase, which catalyzes production of mophinone from morphine, and increased hepatic glutathione level responsible to toxicity. Therefore, wehypothesized that these dual actions of ginseng can be associated with the detoxication of morphine. In addition, the inhibitory or facilitated effects of GTS on electrically evoked contraction in guinea pig ileum (${\mu}$-receptors) and mouse vas deferens(${\delta}$-receptors) were not mediated through opioid receptors, suggesting non-opioid mechanisms. On the hand, antagonism of U-50,488H (${\kappa}$-agonist)-induced antinociception is mediated by serotonergic mechanisms. GTS also inhibited hyperactivity, reverse tolerance (sensitization) and conditioned place preference-induced by psychostimulants such as methamphetamine, cocaine and morphine. On the other hand, GTS reduced the dopamine levels induced by methamphetamine. Moreover, GTS blocked the development of dopamine receptor activation, showing antidopaminergic effect. We suggest that GTS prevent the methamphetamine-induced striatal dopaminergic neurotoxicity. In addition, Ginsenoside also attenuates morphine-induced CAMP signaling pathway. These results suggested that GTS might be useful for the therapy of the adverse actions of drugs with abuse liability.

• The Korean Journal of Physiology and Pharmacology
• /
• v.2 no.6
• /
• pp.687-693
• /
• 1998

This study was performed to examine the mean arterial pressure and nociceptive jaw opening reflex after microinjection of glutamate into the amygdala in freely moving rats, and to investigate the mechanisms of antinociceptive action of amygdala. Animals were anesthetized with pentobarbital sodium (40 mg/kg, ip). A stainless steel guide cannula (26 gauge) was implanted in the amygdala and lateral ventricle. Stimulating and recording electrodes were implanted into each of the incisor pulp and anterior digastric muscle. Electrodes were led subcutaneously to the miniature cranial connector sealed on the top of the skull with acrylic resin. After 48 hours of recovery from surgery, mean arterial pressure and digastric electromyogram (dEMG) were monitored in freely moving rats. Electrical shocks (200 ${\mu}sec$ duration, $0.5{\sim}2$ mA intensity) were delivered at 0.5 Hz to the dental pulp every 2 minutes. After injection of 0.35 M glutamate into the amygdala, mean arterial pressure was increased by $8{\pm}2$ mmHg and dEMG was suppressed to $71{\pm}5%$ of the control. Injection of 0.7 M glutamate elevated mean arterial pressure by $25{\pm}5$ mmHg and suppressed dEMG to $20{\pm}7%$ of the control. The suppression of dEMG were maintained for 30 minutes. Naloxone, an opioid receptor antagonist, inhibited the suppression of dEMG elicited by amygdaloid injection of glutamate from $28{\pm}4\;to\;68{\pm}5%$ of the control. Methysergide, a serotonin receptor antagonist, also inhibited the suppression of dEMG from $33{\pm}5\;to\;79{\pm}4%$ of the control. However, phentolamine, an ${\alpha}-adrenergic$ receptor antagonist, did not affect the suppression of dEMG. These results suggest that the amygdala can modulate both cardiovascular and nociceptive responses and that the antinociception of amygdala seems to be attributed to an augmentation of descending inhibitory influences on nociceptive pathways via serotonergic and opioid pathways.

• Journal of Ginseng Research
• /
• v.14 no.2
• /
• pp.178-186
• /
• 1990

The analgesic effect of morphine was antagonized and the development of tolerance was suppressed by the modification of the neurologic function in the animals treated with ginseng saponins The activation of the spinal descending inhibitory systems as well as the supraspinal structures by the administration of morphine was inhibited in the animals treated with ginseng saponine intracerebrally or intrathecally. The development of morphine tolerance and dependence, and the abrupt expression of naloxone inducted abstinence syndrom were also inhibited by ginsenoside Rb1, Rb2, Rg1 and Re. These results suggest that ginsenoside Rbl, Hbs, Rgl and Re are the bioactive components of panax ginseng on the inhibition of the development of morphine tolerance and dependence, and the inhibition of abrupt abstinence sindrome. In addition, further research on the minor components of Pnnnxkinsenl should be investigated. A single or daily treatment with ginseng saponins did not induce any appreciable changes in the brain in level of monoamines at the variolls time intervals and at the various day intervals, respectively. The inhibitory or facilitated effects of ginseng saponins on electrically evoked contractions in guinea pig ileum ($\mu$-receptor) and mouse vats deferens ($\delta$-receptor) were not mediated through opioid receptors. The antagonism of a $\chi$ receptor agonist, U-50, 488H was also not mediated through opioid receptors in the animals treated with ginseng saponins, but mediated through serotonergic mechanisms. Ginseng saponins inhibited morphine 6-dehydrogenase which catalyzed the production of morphinone from morphine, and increased hepatic glutathione contents for the detoxication of morphinone. This result suggests that the dual action of the above plays an important role in the inhibition of the development of morphine tolerance and dependence.

• The Korean Journal of Pain
• /
• v.14 no.2
• /
• pp.150-155
• /
• 2001

Background: Tramadol is known to be a weak opioid. However, it has also been shown that tramadol is an effective norepinephrine and serotonin uptake blocker, which may be effective in the treatment of neuropathic pain. The present study was undertaken in order to assess the antinociceptive action of tramadol and to investigate possible antinociceptive mechanisms by using antagonists in an animal neuropathic pain models in rats. Methods: Rats were prepared with tight ligation at the left 5 and 6th lumbar spinal nerves (Kim and Chung's neuropathic pain model). The antinociceptive effects of tramadol (10, 20, and 50 mg/kg i.p.) in rats with neuropathic pain were assessed. Additionally, following coadministration of antagonists such as naloxone (1 mg/kg i.p.), yohimbine (1 mg/kg i.p.) and ritanserin (1 mg/kg i.p.) with 50 mg/kg of tramadol, the responses to mechanical and thermal stimuli were measured over a two-hour period. Results: Tramadol displayed potent antinociceptive effects in a dose-dependent manner on rats with neuropathic pain (P < 0.05). The effects of tramadol were inhibited by coadministered naloxone and yohimbine in rats with mechanical and thermal allodynia, respectively (P < 0.05). However, there were no significant changes in the pain behaviors in the case of ritanserin. Conclusions: Tramadol showed significant antinociceptive effects in rats with regards to neuropathic pain against both mechanical and thermal allodynia. The antinociceptive effect on the mechanical stimuli is medicated via an opioid receptor. However, it appears that the antinociceptive effects on thermal allodynia are mediated via a noradrenalin receptor vice a serotonergic receptor.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.1
• /
• pp.65-70
• /
• 2012

Synaptic long-term potentiation (LTP) and long-term depression (LTD) have been studied as mechanisms of ocular dominance plasticity in the rat visual cortex. Serotonin (5-hydroxytryptamine, 5-HT) inhibits the induction of LTP and LTD during the critical period of the rat visual cortex (postnatal 3~5 weeks). However, in adult rats, the increase in 5-HT level in the brain by the administration of the selective serotonin reuptake inhibitor (SSRI) fluoxetine reinstates ocular dominance plasticity and LTP in the visual cortex. Here, we investigated the effect of 5-HT on the induction of LTP in the visual cortex obtained from 3- to 10-week-old rats. Field potentials in layer 2/3, evoked by the stimulation of underlying layer 4, was potentiated by theta-burst stimulation (TBS) in 3- and 5-weekold rats, then declined to the baseline level with aging to 10 weeks. Whereas 5-HT inhibited the induction of LTP in 5-week-old rats, it reinstated the induction of N-methyl-D-aspartate receptor (NMDA)-dependent LTP in 8- and 10-week-old rats. Moreover, the selective SSRI citalopram reinstated LTP. The potentiating effect of 5-HT at 8 weeks of age was mediated by the activation of 5-$HT_2$ receptors, but not by the activation of either 5-$HT_{1A}$ or 5-$HT_3$ receptors. These results suggested that the effect of 5-HT on the induction of LTP switches from inhibitory in young rats to facilitatory in adult rats.

• Archives of Pharmacal Research
• /
• v.28 no.9
• /
• pp.995-1001
• /
• 2005

Morphine-induced analgesia has been shown to be antagonized by ginseng total saponins (GTS), which also inhibit the development of analgesic tolerance to and physical dependence on morphine. GTS is involved in both of these processes by inhibiting morphine-6-dehydrogenase, which catalyzes the synthesis of morphinone from morphine, and by increasing the level of hepatic glutathione, which participates in the toxicity response. Thus, the dual actions of ginseng are associated with the detoxification of morphine. In addition, the inhibitory or facilitated effects of GTS on electrically evoked contractions in guinea pig ileum (I-L-receptors) and mouse vas deferens $(\delta-receptors)$ are not mediated through opioid receptors, suggesting the involvement of non-opioid mechanisms. GTS also attenuates hyperactivity, reverse tolerance (behavioral sensitization), and conditioned place preference induced by psychotropic agents, such as methamphetamine, cocaine, and morphine. These effects of GTS may be attributed to complex pharmacological actions between dopamine receptors and a serotonergic/adenosine $A_{2A}1\delta-opioid$ receptor complex. Ginsenosides also attenuate the morphine-induced cAMP signaling pathway. Together, the results suggest that GTS may be useful in the prevention and therapy of the behavioral side effects induced by psychotropic agents.

• Journal of the Korean society of biological therapies in psychiatry
• /
• v.24 no.3
• /
• pp.129-141
• /
• 2018

Suicide is a behavior that is intended to cause death by itself and requires medical treatment, resulting in suicidal attempt or completion. Suicide causes loss of life, damages the body, costs a lot of medical expenses, and causes families to fall into sorrow and suffering therefore this suicide is a huge loss to family and society. There have been attempts to reduce and prevent suicide by understanding the mechanism of suicide. The mechanism of suicide can be thought of as psychological mechanism and biological mechanism. In the past, if we considered the psychological and biological mechanisms separately, the development of neuroscience now connects and integrates these two. Psychological factors affect biological factors and biological temperaments also affect perception or thinking about the situation and increase psychological vulnerability. Distant factors in suicidal behavior-such as childhood adversity and family and genetic predisposition-increase the lifetime risk of suicide. They alter the response to stress and other processes through changes in gene expression and regulation of emotional and behavioral characteristics. Distant factors affect the biological system and consequently changes in these systems can increase the risk of suicide. In other words, the distal factor does not directly induce suicidal behavior but rather acts indirectly through developmental or mediating factors. These mediating factors are impulsive aggressive and anxious trait, and chronic use of substances. The mechanism of this disorder is the abnormality of the serotonin system and the abnormality of the lipid level. Proximal factors are associated with the onset of suicide events and include changes in the major neurotransmitter systems, inflammatory changes, and dysfunction of glial cells in the brain. A series of studies, including a variety of research methods and postmortem and in-vivo imaging studies, show the impairment of the serotonergic neurotransmitter system and hypothalamic-pituitary-adrenal axis stress response system for suicidal behavior. These disorders lead to suicidal behavior due to difficulty in cognitive control of mood, pessimism, reactive aggression, abnormality in problem solving abilities, excessive response to negative social signals, severe emotional distress, and cognitive dysregulation of suicidal ideation.

• Journal of Ginseng Research
• /
• v.47 no.4
• /
• pp.552-560
• /
• 2023

Background: Ginseng Radix (Panax ginseng Meyer, Araliaceae) has been used medicinally to treat the brain and nervous system problems worldwide. Recent studies have revealed physiological effects that could potentially benefit cognitive performance or mood. The present study aimed to investigate the antidepressant effects of Korean red ginseng water extract (KGE) and its active component in an unpredictable chronic mild stress (UCMS)-induced animal model and elucidate the underlying mechanisms. Methods: The antidepressant potential of the UCMS model was evaluated using the sucrose preference test and open field tests. The behavioral findings were further corroborated by the assessment of neurotransmitters and their metabolites from the prefrontal cortex and hippocampus of rats. Three doses of KGE (50, 100, and 200 mg/kg) were orally administered during the experiment. Furthermore, the mechanism underlying the antidepressant-like action of KGE was examined by measuring the levels of brain-derived neurotrophic factor (BDNF)/CREB, nuclear factor erythroid 2-related factor 2 (Nrf2), and Kelch-like ECH-associated protein 1 (Keap1) proteins in the prefrontal cortex of UCMS-exposed rats. Results: KGE treatment normalized UCMS-induced depression-related behaviors. Neurotransmitter studies conducted after completing behavioral experiments demonstrated that KGE caused a reduction in the ratio of serotonin and dopamine, indicating a decrease in serotonin and dopamine turnover. Moreover, the expression of BDNF, Nrf2, Keap1 and AKT were markedly increased by KGE in the prefrontal cortex of depressed rats. Conclusion: Our results provide evidence that KGE and its constituents exert antidepressant effects that mediate the dopaminergic and serotonergic systems and expression of BDNF protein in an animal model.

• The Korean Journal of Pain
• /
• v.37 no.1
• /
• pp.26-33
• /
• 2024

Background: Sitagliptin is an antidiabetic drug that inhibits dipeptidyl peptidase-4 enzyme. This study aimed to investigate the antinociceptive and anti-inflammatory effects of sitagliptin in formalin and carrageenan tests and determine the possible mechanism(s) of its antinociceptive activity. Methods: Male Swiss mice (25-30 g) and male Wistar rats (180-220 g) were used for formalin and carrageenan tests, respectively. In the formalin test, paw licking time and in the carrageenan test, paw thickness were considered as indexes of pain behavior and inflammation respectively. Three doses of sitagliptin (2.5, 5, and 10 mg/kg) were used in these tests. Also, several antagonists and enzyme inhibitors were used to evaluate the role of adrenergic, serotonergic, dopaminergic, and opioid receptors as well as the NO/cGMP/K_ATP pathway in the antinociceptive effect of sitagliptin (5 mg/kg). Results: Sitagliptin showed significant antinociceptive and anti-inflammatory effects in the formalin and carrageenan tests respectively. In the carrageenan test, all three doses of sitagliptin significantly (P < 0.001) reduced paw thickness. Pretreatment with yohimbine, prazosin, propranolol, naloxone, and cyproheptadine could not reverse the antinociceptive effect of sitagliptin (5 mg/Kg), which indicates that adrenergic, opioid, and serotonin receptors (5HT₂) are not involved in the antinociceptive effects. L-NAME, methylene blue, glibenclamide, ondansetron, and sulpiride were able to reverse this effect. Conclusions: NO/cGMP/K_ATP, 5HT₃ and D₂ pathways play an important role in the antinociceptive effect of sitagliptin. Additionally significant anti-inflammatory effects observed in the carrageenan test might contribute in reduction of pain response in the second phase of the formalin test.

• Korean Journal of Biological Psychiatry
• /
• v.5 no.2
• /
• pp.253-262
• /
• 1998

Objectives : Risperidone, an atypical antipsychitics which blocks both dopaminergic and serotonergic receptors, have a good response to the negative symptoms as well as positive symptoms, and improve cognitive dysfunction of schizophrenic patients. Furthermore, it has few extrapyramidal side effects and tardive dyskinesia. Although it had been reported that the atypical antipsychotics have less effect on prolactin(PRL) than the classical antipsychotics, we could experience PRL-associated symptoms such as amenorrhea, galactorrhea and hyperprolactinemia in practice. Therefore, we tried to identify the sex differences of risperidone-induced hyperprolactinemia, to evaluate factors affecting PRL levels, and to know the association between cognitive disorders and PRL. Methods : The baseline levels of PRL and TSH prior to risperidone administration were measured by enzyme immunoassay method for 50 patients(25 ma-les and 25 females) admitted with schizophrenia, schizoaffective disorder or schizophreniform disorder according to the DSM-IV classification, and the measurements of PRL were repeated on the 2nd and the 4th wks of risperidone administration. Concomitantly, the severity of psychotic symptoms using CGI, BPRS and PANSS, and the cognitive dysfunction using PANSS-CF were assessed prior to, on the 2nd and the 4th wks of risperidone administration. The PRL and TSH levels of 54 healthy controls(29 males and 25 females) who had no medical, neurological and psychiatric illnesses were also evaluated. Furthermore, the correlation with the psychiatric diagnosis, education, age, sex, duration of illnesses, risperidone dosage, duration of risperdone administration, TSH concentration, cognitive function, severity of psychotic symptoms were also identified. Results : 1) The baseline PRL levels of female schizophrenics($74.3{\pm}49.6ng/ml$) were significantly(p<0.005) higher than those of males($36.3{\pm}24.6ng/ml$), which were significantly(p<0.0001 respectively) higher than those of controls(females $16.9{\pm}6.1ng/ml$, males $13.3{\pm}4.9ng/ml$). The PRL levels measured on the 2nd wks(females $133.7{\pm}47.8ng/ml$, males $56.9{\pm}23.6ng/ml$) and on the 4th wks(females $146.1{\pm}45.9ng/ml$, males $70.0{\pm}31.5ng/ml$) after risperidone administration were significantly(p<0.0001 respectively) higher in females. The mean dosages of risperidone on the 2nd wks were $3.8{\pm}1.7mg$(2-6mg) for the females and $4.0{\pm}1.6mg$(2-6mg) for the males, and on the 4th wks were $4.5{\pm}2.1mg$(2-8mg) for the females and $5.4{\pm}2.2mg$(2-8mg) for the males. 2) The rise of PRL levels were positively correlated with increased risperidone dosage in males(${\gamma}$=0.307 on the 2nd wks and ${\gamma}$=0.280 on the 4th wks), while they were not correlated with dosages in females. For the females, the PRL levels were negatively correlated(${\gamma}$=-0.320) with decrease of TSH concentration. The baseline PRL levels were not correlated with age, education, duration of illnesses, psychopathology, cognitive disorders in both males and females, while it was negatively correlated with TSH levels only in females(${\gamma}$=-0.320). 3) The cognitive dysfunction was not correlated with PRL levels in males, while PANSS-CF scores were negatively correlated with PRL levels(${\gamma}$=-0.220 on the 2nd wks and ${\gamma}$=-0.366 on the 4th wks) in females. The psychopathology was positively correlated with cognitive dysfunction in both males and females. Therefore, the risperidone-induced cognitive improvement seemed to be correlated with improvement of psychopathology in both males and females, and with increase in PRL levels only in females. Conclusions : The fact that the serum PRL levels of schizophrenics were higher than those of controls, especially in females suggested that it could be related with risperidone dosage in males and with primary pathological process in females. The risperidone-associated cognitive improvement seemed to be related with general improvement of psychopathology as well as the rise of PRL levels especially in females. The facts that the effect of risperidoneinduced hyperprolactinemia and the cognitive function were more in females suggested that somewhat different mechanisms could be exerted on them.