The purpose of this study was to investigate the effects of α₂ adrenergic receptor agonist dexmedetomidine on withdrawal symptoms in alcohol-dependent rats and the underlying mechanism, so as to provide a scientific basis for the treatment of alcohol withdrawal syndrome (AWS). Adult Sprague-Dawley (SD) male rats were orally administered with 6% aqueous alcohol continuously for 28 d to establish alcohol drinking model, and then stopped drinking to induce AWS. Enzyme-linked immunosorbent assay (ELISA) was used to determine the content of norepinephrine (NE) in the locus coeruleus and hippocampus of rats. Dexmedetomidine (5, 10, and 20 μg/kg) was intraperitoneally injected respectively when the rats showed significant AWS. In some rats, α₂ adrenergic receptor antagonist yohimbine was injected into hippocampus in advance. The results showed that, compared with the control group, the 6 h withdrawal group exhibited significantly increased AWS score and amount of repeat drinking. The NE contents in hippocampus and locus coeruleus of the last drinking and the 6 h withdrawal groups were significantly increased compared with those of the control group. Dexmedetomidine intervention significantly decreased AWS score and hippocampus NE content in the 6 h withdrawal group, while yohimbine could reverse these effects of dexmedetomidine. These results suggest that dexmedetomidine might improve the withdrawal symptoms in alcohol-dependent rats via activating α₂ adrenergic receptor.
Adrenergic alpha-2 Receptor Agonists/therapeutic use* ; Alcoholism/drug therapy* ; Animals ; Dexmedetomidine/therapeutic use* ; Hippocampus/metabolism* ; Male ; Norepinephrine ; Rats ; Rats, Sprague-Dawley ; Receptors, Adrenergic, alpha-2/metabolism* ; Substance Withdrawal Syndrome/drug therapy* ; Yohimbine/pharmacology*

To investigate the effect of Rehmanniae Radix on depression-like behavior and monoamine neurotransmitters of chronic unpredictable mild stress(CUMS) model rats. CUMS combined with isolated feeding was used to induce the depression model of rats. The depression-like behavior of rats was evaluated by sucrose preference test, open field test, and forced swim test. Hematoxylin-Eosin(HE) staining was used to investigate the pathological changes of neurons in the CA1 and CA3 area of hippocampus. Ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS) was used to detect the contents of 5-hydroxytryptamine(5-HT), 5-hydroxyindoleacetic acid(5-HIAA), dopamine(DA), 3,4-dihydroxyphenylacetic acid(DOPAC), homovanillic acid(HVA), norepinephrine(NE), and 3-methoxy-4-hydroxyphenyl glycol(MHPG) in rats. Western blot was used to detect the protein expressions of tryptophan hydroxylase 2(TPH2), serotonin transporter(SERT), and monoamine oxidase A(MAO-A) in the hippocampus of rats. Compared with the normal group, depressive-like behavior of rats was obvious in the model group. The arrangements of neurons in the CA1 and CA3 area of hippocampus were loose and disorderly. The levels of 5-HT, 5-HIAA, and 5-HT/5-HIAA in the hippocampal area were decreased(P<0.01). The protein expression of TPH2 was decreased(P<0.01), but those of SERT and MAO-A were increased(P<0.01). In the Rehmanniae Radix groups with 1.8 g·kg~(-1) and 7.2 g·kg~(-1), the depression-like behavior of CUMS rats and pathological changes of neurons in CA1, CA3 area of hippocampus were improved. The protein expression of TPH2(P<0.05, P<0.01) was increased, and those of SERT and MAO-A were down-regulated(P<0.05, P<0.01). The levels of 5-HT, 5-HIAA, and 5-HT/5-HIAA in hippocampus were increased(P<0.05, P<0.01). The changes in DA, DOPAC, HVA, DA/(DOPAC +HVA), NE, DHPG, and NE/DHPG were not statistically significant. The results suggested that Rehmanniae Radix improved depression-like behavior of CUMS rats, and the mechanism might be related to the regulation of synthesis, transportation, and metabolism of 5-HT neurotransmitter in the hippocampus.
3,4-Dihydroxyphenylacetic Acid/pharmacology* ; Animals ; Antidepressive Agents/therapeutic use* ; Chromatography, Liquid ; Depression/drug therapy* ; Disease Models, Animal ; Dopamine ; Eosine Yellowish-(YS)/pharmacology* ; Hematoxylin/pharmacology* ; Hippocampus/metabolism* ; Homovanillic Acid/pharmacology* ; Hydroxyindoleacetic Acid/metabolism* ; Methoxyhydroxyphenylglycol/pharmacology* ; Monoamine Oxidase/metabolism* ; Neurotransmitter Agents/metabolism* ; Norepinephrine/pharmacology* ; Plant Extracts ; Rats ; Rehmannia/chemistry* ; Serotonin/metabolism* ; Serotonin Plasma Membrane Transport Proteins/pharmacology* ; Stress, Psychological/metabolism* ; Tandem Mass Spectrometry ; Tryptophan Hydroxylase/metabolism*

Cerebellar Purkinje cells (PCs) exhibit two types of discharge activities: simple spike (SS) and complex spike (CS). Previous studies found that noradrenaline (NA) can inhibit CS and bidirectionally regulate SS, but the enhancement of NA on SS is overwhelmed by the strong inhibition of excitatory molecular layer interneurons. However, the mechanism underlying the effect of NA on SS discharge frequency is not clear. Therefore, in the present study, we examined the mechanism underlying the increasing effect of NA on SS firing of PC in mouse cerebellar cortex in vivo and in cerebellar slice by cell-attached and whole-cell recording technique and pharmacological methods. GABA_A receptor was blocked by 100 µmol/L picrotoxin in the whole process. In vivo results showed that NA significantly reduced the number of spikelets of spontaneous CS and enhanced the discharge frequency of SS, but did not affect the discharge frequency of CS. In vitro experiments showed that NA reduced the number of CS spikelets and after hyperpolarization potential (AHP) induced by electrical stimulation, and increased the discharge frequency of SS. NA also reduced the amplitude of excitatory postsynaptic current (EPSC) of parallel fiber (PF)-PC and significantly increased the paired-pulse ratio (PPR). Application of yohimbine, an antagonist of α2-adrenergic receptor (AR), completely eliminated the enhancing effect of NA on SS. The α2-AR agonist, UK14304, also increased the frequency of SS. The β-AR blocker, propranolol, did not affect the effects of NA on PC. These results suggest that in the absence of GABA_A receptors, NA could attenuate the synaptic transmission of climbing fiber (CF)-PC via activating α2-AR, inhibit CS activity and reduce AHP, thus enhancing the SS discharge frequency of PC. This result suggests that NA neurons of locus coeruleus can finely regulate PC signal output by regulating CF-PC synaptic transmission.
Action Potentials/physiology* ; Animals ; Cerebellar Cortex/metabolism* ; Cerebellum/metabolism* ; Mice ; Norepinephrine/pharmacology* ; Purkinje Cells/metabolism* ; Receptors, Adrenergic, alpha-2/metabolism* ; Receptors, GABA-A/metabolism*

A large number of β-adrenergic receptor (β-AR) agonists and antagonists are widely used in the treatment of cardiovascular diseases and other diseases. Nonetheless, it remains unclear whether these commonly used β-AR drugs can activate downstream β- arrestin-biased signaling pathways. The objective of this study was to investigate β-arrestin2 recruitment effects of β-AR agonists and antagonists that were commonly used in clinical practice. We used TANGO (transcriptional activation following arrestin translocation) assay to detect the β-arrestin2 recruitment by β-AR ligands in HEK293 cell line (HTLA cells) stably transfected with tetracycline transactivator protein (tTA) dependent luciferase reporter and β-arrestin2-TEV fusion gene. Upon activation of β-AR by a β-AR ligand, β-arrestin2 was recruited to the C terminus of the receptor, followed by cleavage of the G protein-coupled receptors (GPCRs) fusion protein at the TEV protease-cleavage site. The cleavage resulted in the release of tTA, which, after being transported to the nucleus, activated transcription of the luciferase reporter gene. The results showed that β-AR non-selective agonists epinephrine, noradrenaline and isoprenaline all promoted β-arrestin2 recruitment at β1-AR and β2-AR. β1-AR selective agonists dobutamine and denopamine both promoted β-arrestin2 recruitment at β1-AR. β2-AR selective agonists procaterol and salbutamol promoted β-arrestin2 recruitment at β2-AR. β-AR non-selective antagonists alprenolol and pindolol promoted β-arrestin2 recruitment at β1-AR. β1-AR selective antagonists celiprolol and bevantolol showed β-arrestin2 recruitment at β1-AR. β2-AR selective antagonists butoxamine showed β-arrestin2 recruitment at β1-AR. These results provide some clues for the potential action of β-AR drugs, and lay a foundation for the screening of β-arrestin-biased β-AR ligands.
Humans ; beta-Arrestin 2/metabolism* ; HEK293 Cells ; Adrenergic beta-Agonists/pharmacology* ; Isoproterenol/pharmacology* ; Receptors, Adrenergic, beta-2/metabolism* ; Norepinephrine/pharmacology*

Anxiety disorders are a common mental illness that seriously endangered physical and mental health of human beings. The etiology of anxiety disorders is closely related to the abnormality of monoamines neurotransmitters, amino acids neurotransmitters and neuropeptides. The long-term use of anti-anxiety chemical drugs has some adverse effects, such as constipation, muscle relaxation, lethargy, tolerance and withdrawal symptoms. However, traditional Chinese medicines have advantages of multi-component, multi-target coordination, with less adverse reactions. Therefore, it is a promising prospect to develop novel anti-anxiety drugs from traditional Chinese medicines and formulas. This article reviewed some traditional Chinese medicines and formulas that can relieve anxiety symptoms. These include traditional Chinese medicines(Panax ginseng, Lycium ruthenium, Morus alba, Bupleurum plus dragon bone oyster soup, Chailong Jieyu Pills, and Naogongtai Formulas) with the effect on monoamine neurotransmitters, such as serotonin, dopamine, and norepinephrine; traditional Chinese medicines(Rehmannia glutinosa, Ziziphus jujuba Mill. var. spinosa, Jielv Anshen Decoction, Baixiangdan Capsules, Antianxietic Compound Prescription Capsules) with the effect on amino acid neurotransmitters, such as glutamic acid, γ-aminobutyrc acid; and traditional Chinese medicines(P. ginseng, Xiaoyao San, Shuyu Ningxin Decoction)with the effect on neuropeptide Y pathway, with the aim to provide theoretical basis for the further development of some novel and more effective anti-anxiety therapeutics from traditional Chinese medicine and formulas.
Anti-Anxiety Agents/pharmacology* ; Drugs, Chinese Herbal/pharmacology* ; Humans ; Medicine, Chinese Traditional ; Neurotransmitter Agents ; Norepinephrine ; Serotonin

Over the last 5 years, the Korean Ministry of Food and Drug Safety has approved four anti-obesity drugs for long-term weight management. In this review, the mechanisms of action and clinical applications of lorcaserin, naltrexone/bupropion, liraglutide, and phentermine/topiramate have been clarified. Lorcaserin stimulates proopiomelanocortin/cocaine- and amphetamine-regulated transcript neurons in the arcuate nucleus. Naltrexone/bupropion reduces body weight by controlling the hedonic reward system of food intake. The hypophagic effect of liraglutide depends on the direct activation of the proopiomelanocortin/cocaine- and amphetamine-regulated transcript neurons and indirect suppression of neuropeptide Y/agouti-related peptide neurons through gammaaminobutyric acid-dependent signaling, with an additional thermogenic effect. Phentermine/topiramate induces weight loss by elevating the norepinephrine levels in the hypothalamus, reducing energy deposition in the adipose tissue and skeletal muscle, and elevating the corticotropin-releasing hormone in the hypothalamus. In patients with high cardiovascular risks or type 2 diabetes mellitus, lorcaserin and liraglutide are appropriate. In patients with mood disorders, naltrexone/bupropion could be considered as the first choice of therapy. Notably, lorcaserin and liraglutide are neutral in the aspect of sleep disorder. In case of obese individuals with obstructive sleep apnea, liraglutide or phentermine/topiramate would be selected as the treatment option. These four drugs should be used after considering the patients' co-morbidities of obesity.
Adipose Tissue ; Anti-Obesity Agents ; Arcuate Nucleus of Hypothalamus ; Body Weight ; Corticotropin-Releasing Hormone ; Diabetes Mellitus, Type 2 ; Eating ; Humans ; Hypothalamus ; Korea ; Liraglutide ; Mood Disorders ; Muscle, Skeletal ; Neurons ; Neuropeptides ; Norepinephrine ; Obesity ; Pharmacology ; Reward ; Sleep Apnea, Obstructive ; Sleep Wake Disorders ; Weight Loss

OBJECTIVETo observe the preventive effect of different compatibilities of Ramulus Cinnamomi (RC) and Radix Paeomiae alba (RPA) in Guizhi Decoction (GZD) on neurotransmitters and their rate-limiting enzymes, and neurotrophic factors of cardiac sympathetic denervation model rats induced by 6-hydroxydopamine (6-OHDA).

METHODSTotally 54 male Wistar rats were randomly divided into 6 groups, i.e., the blank control group, the model group, the methycobal group, the 2:1 (RC/RPA) Guishao group, the 1:2 Guishao group, and the 1:1 Guishao group, 9 in each group. Sympathetic denervation was induced by intraperitoneal injection of 6-OHDA for three successive days. Rats in the methycobal group and GZD groups were administered with corresponding decoction by gastrogavage 1 week before modeling (methycobal at the daily dose 0.15 mg/kg; GZD at the daily dose of 4.0, 5.5, 5.5 g crude drugs/kg for GZD 1:1, 1:2, and 2:1 groups). All medication lasted for 10 successive days. Levels of norepinephrine (NE), tyrosine hydroxylase (TH), choline acetyl-transferase (ChAT), nerve growth factor (NGF), growth associated protein43 (GAP-43) and ciliary neurotrophic factor (CNTF) in myocar- dial homogenates of right atrium and ventricular septum were detected by ELISA.

RESULTSCompared with the blank control group, levels of NE, TH, TH/ChAT ratio, and GAP-43 in myocardial homogenates of right atrium and ventricular septum decreased in the model group, and level of NGF increased (P < 0.01, P < 0.05). Compared with the model group, levels of NE and GAP-43 increased in the right atrium and interventricular septum; NGF level of the ventricular septum decreased in the methycobal group and each GZD groups. TH and TH/ChAT ratio in the right atrium increased in the 2:1 Guishao group and the 1:2 Guishao group (P < 0.01, P < 0.05); NGF levels in the right atrium and interventricular septum decreased only in the 1:1 Guishao group (P < 0.01, P< 0.05). Compared with the methycobal group, levels of NE, TH, and GAP-43 in the right atrium and interventricular septum increased, and NGF levels in the right atrium and interventricular septum decreased in the 1:1 Guishao group (P < 0.05). Compared with the methycobal group, levels of NE and GAP-43 in interventricular septum increased in the 2:1 Guishao group (P < 0.05).

CONCLUSIONGZD (with the proportion between RC and RPA 2:1 and 1:1) could improve contents of neurotransmitters and their rate-limiting enzymes, as well as neurotrophic factors in cardiac sympathetic denervation model rats induced by 6-OHDA, alleviate cardiac sympathetic denervation induced by 6-OHDA, and maintain the balance of sympathetic-vagal nerve system.

Animals ; Choline O-Acetyltransferase ; metabolism ; Ciliary Neurotrophic Factor ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; GAP-43 Protein ; metabolism ; Heart ; drug effects ; innervation ; Male ; Myocardium ; metabolism ; Nerve Growth Factor ; metabolism ; Norepinephrine ; metabolism ; Oxidopamine ; adverse effects ; Random Allocation ; Rats ; Rats, Wistar ; Sympathectomy ; Tyrosine 3-Monooxygenase ; metabolism

OBJECTIVETo compare the effect of Shen-Fu Injection (SFI) and epinephrine on the expression of sarcoplasmic reticulum Ca(2+) ATPase 2a (SERCA2a) in a pig model with post-resuscitation myocardial dysfunction.

METHODSVentricular fibrillation (VF) was electrically induced in Wu-zhi-shan miniature pigs. After 8 min of untreated VF and 2 min of cardiopulmonary resuscitation (CPR), all animals were randomly administered a bolus injection of saline placebo (SA group, n=10), SFI (0.8 mg/kg, SFI group, n=10) or epinephrine (20 μg/kg, EPI group, n=10). After 4 min of CPR, a 100-J shock was delivered. If the defibrillation attempt failed to attain restoration of spontaneous circulation (ROSC), manual chest compressions were rapidly resumed for a further 2 min followed by a second defibrillation attempt. Hemodynamic variables were recorded, and plasma concentrations of catecholamines were measured. Adenylate cyclase (AC), cyclic adenosine monophosphate (cAMP) and the expressions of β1-adrenoceptor (AR) and SERCA 2a were determined.

RESULTSCardiac output, left ventricular dp/dtmax and negative dp/dtmax were significantly higher in the SFI group than in the SA and EPI groups at 4 and 6 h after ROSC. The expression of β1-AR and SERCA2a at 24 h after ROSC were significantly higher in the SFI group than in the SA and EPI groups (P<0.05 or P<0.01).

CONCLUSIONSThe administration of epinephrine during CPR decreased the expression of SERCA2a and aggravated postresuscitation myocardial function (P<0.01). SFI attenuated post-resuscitation myocardial dysfunction, and the mechanism might be related to the up-regulation of SERCA2a expression.

Adenylyl Cyclases ; metabolism ; Animals ; Blotting, Western ; Cardiac Output ; drug effects ; Cardiopulmonary Resuscitation ; Cyclic AMP ; metabolism ; Dopamine ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Enzyme-Linked Immunosorbent Assay ; Epinephrine ; blood ; Heart Ventricles ; drug effects ; metabolism ; physiopathology ; Hemodynamics ; drug effects ; Injections ; Male ; Myocardium ; enzymology ; pathology ; Norepinephrine ; blood ; Receptors, Adrenergic, beta-1 ; metabolism ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; metabolism ; Swine ; Swine, Miniature ; Up-Regulation ; drug effects

The present study attempted to test a novel hypothesis that Ca(2+) sparks play an important role in arterial relaxation induced by tacrolimus. Recorded with confocal laser scanning microscopy, tacrolimus (10 µmol/L) increased the frequency of Ca(2+) sparks, which could be reversed by ryanodine (10 µmol/L). Electrophysiological experiments revealed that tacrolimus (10 µmol/L) increased the large-conductance Ca(2+)-activated K(+) currents (BKCa) in rat aortic vascular smooth muscle cells (AVSMCs), which could be blocked by ryanodine (10 µmol/L). Furthermore, tacrolimus (10 and 50 µmol/L) reduced the contractile force induced by norepinephrine (NE) or KCl in aortic vascular smooth muscle in a concentration-dependent manner, which could be also significantly attenuated by iberiotoxin (100 nmol/L) and ryanodine (10 µmol/L) respectively. In conclusion, tacrolimus could indirectly activate BKCa currents by increasing Ca(2+) sparks released from ryanodine receptors, which inhibited the NE- or KCl-induced contraction in rat aorta.
Animals ; Aorta ; cytology ; metabolism ; physiology ; Calcium Signaling ; Cells, Cultured ; Large-Conductance Calcium-Activated Potassium Channels ; metabolism ; Male ; Muscle, Smooth, Vascular ; drug effects ; metabolism ; physiology ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; Norepinephrine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Ryanodine ; pharmacology ; Tacrolimus ; pharmacology ; Vasoconstriction

The efficacy of Chinese herbal formula in treating depression has been proved in many studies. In this study, six different Kaixin San formulas were compared to investigate their effects on central monoamine neurotransmitters of chronic stress rats and against depression based on their different components in plasma, in order to discuss the efficacy-comparability relationship and the possible efficacy mechanism. The classic isolation method and the chronic unpredictable mild stress (CUMS) depression model were combined to investigate the changes in contents in hippocampus and monoamine neurotransmitters (NE, DA, 5-HT) and the components of some formulas in plasma with HPLC and UPLC-Q-TOF-MSE methods. As a result, Dingzhi Xiaowan recorded in Essential Recipes for Emergent Use Worth A Thousand significantly increased the behavioral scores, NE and 5-HT contents in hippocampus and NE, DA and 5-HT contents in cortex, with the best anti-depressant effect. Dingzhi Xiaowan recorded in Complete Records of Ancient and Modern Medical Works showed a notable increase in sucrose preference and open field score in model rats, NE content in hippocampus and NE, DA and 5-HT contents in cortex, with a certain anti anti-depressant effect. Kaixin San recorded in Ishinpo showed remarkable rise in weight of model rats. NE content in hippocampus and DA content in cortex. Puxin Decoction recorded in A Supplement to Recipes Worth A Thousand Gold showed 5-HT content in hippocampus and DA content in cortex. Kaixin San recorded in Yimenfang only showed DA content in cortex. Kaixin Wan recorded in Essential Recipes for Emergent Use Worth A Thousand did not mention the antidepressant effect. According to the results, the formulas' different anti-depressant effects may be related to the different plasma components.
Animals ; Behavior, Animal ; drug effects ; Biogenic Monoamines ; analysis ; Brain Chemistry ; drug effects ; Chronic Disease ; Drugs, Chinese Herbal ; pharmacology ; Male ; Medicine, Chinese Traditional ; Neurotransmitter Agents ; analysis ; Norepinephrine ; analysis ; Rats ; Rats, Sprague-Dawley ; Serotonin ; analysis ; Stress, Psychological ; metabolism