To detect the function and expression of ventricular M3 receptor (M3R) in cerebral-cardiac syndrome (CCS) model rats and to explore the relationship between the expression of M3R and the arrhythmia resulted from CCS, CCS model rats were induced by occluding right middle cerebral artery. ECG was monitored. Intracellular calcium ([Ca2+]i) changes after agitating M3R were recorded by laser scanning confocal microscope. Changes of M3R expression in the ventricular tissue were detected by Western blotting. QRS and QT intervals in CCS group were remarkably longer than that in sham group. According to the results of Western blotting, the level of M3R expression was remarkably lower in CCS group compared with that in the normal group. KCl induced [Ca2+]i increasing in CCS group could be depressed by choline and the effect of choline could be blocked by 4-DAMP. The lower expression of M3R in CCS group may be one of important reasons of arrhythmia resulted from CCS. M3R that depressed the [Ca2+]i increasing agitated by choline may become a new target to cure arrhythmia resulted from CCS.
Animals ; Arrhythmias, Cardiac ; etiology ; metabolism ; pathology ; physiopathology ; Calcium ; metabolism ; Choline ; pharmacology ; Electrocardiography ; Heart Ventricles ; metabolism ; Infarction, Middle Cerebral Artery ; complications ; Male ; Muscarinic Antagonists ; pharmacology ; Myocardium ; metabolism ; ultrastructure ; Myocytes, Cardiac ; metabolism ; Piperidines ; pharmacology ; Potassium Chloride ; pharmacology ; Random Allocation ; Rats ; Rats, Wistar ; Receptor, Muscarinic M3 ; antagonists & inhibitors ; metabolism

PURPOSE: Central nervous system (CNS) and cardiovascular system (CVS) side effects of anticholinergic agents used to treat overactive bladder (OAB) are underreported. Hence, this review aimed to focus on the mechanisms of CNS and CVS side effects of anticholinergic drugs used in OAB treatment, which may help urologists in planning the rationale for OAB treatment. MATERIALS AND METHODS: PubMed/MEDLINE was searched for the key words "OAB," "anticholinergics," "muscarinic receptor selectivity," "blood-brain barrier," "CNS," and "CVS side effects." Additional relevant literature was determined by examining the reference lists of articles identified through the search. RESULTS: CNS and CVS side effects, pharmacodynamic and pharmacokinetic properties, the metabolism of these drugs, and the clinical implications for their use in OAB are presented and discussed in this review. CONCLUSIONS: Trospium, 5-hydroxymethyl tolterodine, darifenacin, and solifenacin seem to have favorable pharmacodynamic and pharmacokinetic properties with regard to CNS side effects, whereas the pharmacodynamic features of darifenacin, solifenacin, and oxybutynin appear to have an advantage over the other anticholinergic agents (tolterodine, fesoterodine, propiverine, and trospium) with regard to CVS side effects. To determine the real-life situation, head-to-head studies focusing especially on CNS and CVS side effects of OAB anticholinergic agents are urgently needed.
Benzhydryl Compounds ; Benzilates ; Benzofurans ; Cardiovascular System* ; Central Nervous System* ; Cholinergic Antagonists* ; Cresols ; Mandelic Acids ; Metabolism ; Pyrrolidines ; Quinuclidines ; Receptors, Muscarinic ; Tetrahydroisoquinolines ; Urinary Bladder, Overactive* ; Solifenacin Succinate

AIMTo observe the effect of activation of M3 receptor on H2O2 induced apoptosis in cultured rat myocytes and to investigate its possible mechanisms.

METHODSIsolated neonatal cardiomyocytes were cultured. Morphologic changes were observed by microscopy. The apoptosis in cardiomyocyte was detected by terminal deoxynucleotide transferase directed d-UTP nick and end labeling (TUNEL) assay. The expression of apoptosis-related protein in Bcl-2 and Fas was measured by immunohistochemistry assay. [Ca2+]i in single cardiomyocyte loaded with Fluo 3-AM was measured by confocal microscope.

RESULTSH2O2-mediated myocyte apoptosis was attenuated by M3 receptor agonist choline (10 mmol x L(-1)). Pretreatment of cardiac myocytes with choline also increased Bcl-2, decreased Fas expression, and inhibited the increase in FI value of [Ca2+]i in H2O2-stimulated cardiac myocytes. However, blockade of M3 receptor by 4DAMP (10 nmol x L(-1)) completely inhibited the effects of choline on H2O2-stimulated cardiac myocytes.

CONCLUSIONActivation of M3 receptor showed protective effect on H2O2-induced apoptosis in cultured rat myocytes and this effect might be related to modulating the expression of some genes including Bcl-2 and Fas as well as the downregulation of [Ca2+]i.

Animals ; Animals, Newborn ; Apoptosis ; drug effects ; Calcium ; metabolism ; Cells, Cultured ; Choline ; pharmacology ; Hydrogen Peroxide ; antagonists & inhibitors ; Myocytes, Cardiac ; cytology ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Wistar ; Receptor, Muscarinic M3 ; agonists ; fas Receptor ; metabolism

Spinal gabapentin has been known to show the antinociceptive effect. Although several assumptions have been suggested, mechanisms of action of gabapentin have not been clearly established. The present study was undertaken to examine the action mechanisms of gabapentin at the spinal level. Male SD rats were prepared for intrathecal catheterization. The effect of gabapentin was assessed in the formalin test. After pretreatment with many classes of drugs, changes of effect of gabapentin were examined. General behaviors were also observed. Intrathecal gabapentin produced a suppression of the phase 2 flinching, but not phase 1 in the formalin test. The antinociceptive action of intrathecal gabapentin was reversed by intrathecal NMDA, AMPA, D-serine, CGS 15943, atropine, and naloxone. No antagonism was seen following administration of bicuculline, saclofen, prazosin, yohimbine, mecamylamine, L-leucine, dihydroergocristine, or thapsigargin. Taken together, intrathecal gabapentin attenuated only the facilitated state. At the spinal level, NMDA receptor, AMPA receptor, nonstrychnine site of NMDA receptor, adenosine receptor, muscarinic receptor, and opioid receptor may be involved in the antinociception of gabapentin, but GABA receptor, L-amino acid transporter, adrenergic receptor, nicotinic receptor, serotonin receptor, or calcium may not be involved.
Acetic Acids/administration & dosage ; Acetic Acids/metabolism ; Acetic Acids/pharmacology* ; Adrenergic Antagonists/metabolism ; Adrenergic alpha-Antagonists/metabolism ; Analgesics/administration & dosage ; Analgesics/metabolism ; Analgesics/pharmacology* ; Animals ; Atropine/metabolism ; Dihydroergocristine/metabolism ; Enzyme Inhibitors/metabolism ; Excitatory Amino Acid Agonists/metabolism ; GABA Antagonists/metabolism ; Injections, Spinal ; Leucine/metabolism ; Male ; Mecamylamine/metabolism ; Muscarinic Antagonists/metabolism ; N-Methylaspartate/metabolism ; Naloxone/metabolism ; Narcotic Antagonists/metabolism ; Nicotinic Antagonists/metabolism ; Pain Measurement ; Quinazolines/metabolism ; Rats ; Rats, Sprague-Dawley ; Serine/metabolism ; Spinal Cord/drug effects* ; Thapsigargin/metabolism ; Triazoles/metabolism ; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/metabolism

Muscarinic receptors play key roles in the control of gastrointestinal smooth muscle activity. However, specific physiological functions of each subtype remain to be determined. In this study, the nonselective cation channel activated by carbachol (ICCh) was examined in circular smooth muscle cells of the guinea pig gastric antrum using patch-clamp technique. 4-DAMP inhibited ICCh dose- dependently with IC50 of 1.1 +/- 0.1 nM (n = 6). GTPgS- induced current, however, was not inhibited by 10 nM 4-DAMP. ICCh was not recorded in pertussis- toxin (PTX)-pretreated smooth muscle cells of gastric antrum. ICCh values in response to 10 mM CCh at a holding potential of 60 mV were -330 32 pA (n=4) and -15 +/- 3 pA (n = 6) in the control and PTX-treated cells, respectively (P<0.01). Sensitivities to nanomolar 4-DAMP and PTX suggest the possible involvement of m4 subtype. Using sequence information obtained from cloned guinea pig muscarinic receptor genes, it is possible to amplify the cDNAs encoding m1-m5 from guinea pig brain tissue. Single cell RT-PCR experiments showed that all five subtypes of muscarinic receptor were present in circular smooth muscle cells of the guinea pig gastric antrum. Together with our previous results showing that Go protein is important for activation of ACh-activated NSC channels, our results suggest that ICCh might be activated by acetylcholine through m4 subtype as well as m2 and m3 subtypes in guinea-pig stomach.
Animals ; Base Sequence ; Carbachol/pharmacology ; Cations ; Cholinergic Agonists/pharmacology ; Dose-Response Relationship, Drug ; Drug Interactions ; Guinea Pigs ; Ion Channels/drug effects/metabolism/physiology ; Muscarinic Antagonists/pharmacology ; Muscle Contraction/drug effects ; Muscle, Smooth/drug effects/*metabolism ; Piperidines/pharmacology ; Receptors, Muscarinic/chemistry/classification/*metabolism ; Stomach/drug effects/*metabolism

OBJECTIVE: To investigate the regulation of atropine to the expression and secretion of TGF-beta2 in retinal pigment epithelium (RPE) cells by observing the changes of those under different treatments of atropine and carbachol. METHODS: D407 cells were cultured conventionally and divided into 4 groups as follows: (1) An experimental group (Group A), cells were pretreated with 10(-4)-10(-8) mol/L atropine for 30 min, and then treated with 10(-5) mol/L carbachol; (2) a negative control group (Group B), cells were treated with 10(-4)-10(-8) mol/L atropine; (3) a positive control group (Group C), cells were treated with 10(-5) mol/L carbachol; (4) a blank control group (Group D). The concentration of TGF-beta2 in the supernate, and the level of TGF-beta2 mRNA and protein were measured by ELISA, RT-PCR, and Western blot after the 24-hour treatment. The data were analyzed by analysis of variance. RESULTS: The levels of TGF-beta2 mRNA and protein in the cytoplasm and the concentration of TGF-beta2 in the supernate in the experimental groups were lower than those of the positive control group. Atropine at 10-4 mol/L could completely inhibit the effect of carbachol at 10-5 mol/L. The effect of atropine was concentration-dependent (F=1,056.897,1,320.170, and 475.657; P<0.001). There was no change of TGF-beta2 level in the cytoplasm and supernate with the treatment of atropine alone (P>0.05). CONCLUSION Carbachol can promote the expression and secretion of TGF-beta2 in human RPE cells and atropine could reverse it effectively, suggesting that M receptor may be involved.
Adult ; Atropine ; pharmacology ; Carbachol ; pharmacology ; Cell Line ; Female ; Humans ; Male ; Muscarinic Antagonists ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Retinal Pigment Epithelium ; cytology ; metabolism ; Transforming Growth Factor beta2 ; genetics ; metabolism ; Young Adult

OBJECTIVE: To observe the inhibitive effect of pirenzepine on form deprivation myopia in guinea pigs and to explore the mechanism of Smad3 signaling pathway and connective tissue growth factor (CTGF) in the inhibition of myopia by pirenzepine. METHODS: Forty 1-week-old guinea pigs of either sex were randomly divided into 4 groups: a control group (Group I), a form deprivation group (Group II), a pirenzepine ophthalmic solution group (Group III), and a sodium chloride ophthalmic solution group (Group IV). Translucent blinders were used in the right eyes of Group II, III and IV. The left eyes were not given any treatment as the normal control group. Covered eyes of Group III and IV were given 3% pirenzepine ophthalmic solution and 0.1% azone ophthalmic solution respectively twice every day. Six weeks later, refraction and axial length were measured at the end of the experiment, and immunohistochemistry and Western blot were used to analyze the expression levels of Smad3 and CTGF in the sclera of all 4 groups. RESULTS: There was no significant difference between Group III and I in relative refraction and changes of axial length (P>0.05). The difference of Group II and IV compared with Group I was statistically significant (P<0.05). The number of Smad3 and CTGF positive cells in the sclera between Group III and I was not significantly different (P>0.05), while the difference in Group II, IV and I was significant (P<0.05). Western blot showed that the expression levels of Smad3 and CTGF in Group II and IV were much lower than those in Group I (P<0.05), but not evident in Group III and I (P>0.05). CONCLUSION Pirenzepine ophthalmic solution can inhibit the development of form deprivation myopia. Pirenzepine may affect Smad3 signaling pathway in the sclera by inhibiting the development of form deprivation myopia.
Animals ; Connective Tissue Growth Factor ; metabolism ; Guinea Pigs ; Humans ; Muscarinic Antagonists ; administration & dosage ; Myopia ; prevention & control ; Pirenzepine ; administration & dosage ; Random Allocation ; Sensory Deprivation ; Signal Transduction ; drug effects ; Smad3 Protein ; metabolism

The modulation of ACh on delayed rectifier-like potassium currents (I(K)) was studied in freshly dissociated cerebral cortical neurons using the whole-cell patch-clamp technique. Wistar rats between 10- and 14-day old of both sexes were used. After rats were decapitated, their brains were quickly removed, iced, and then manually cut into 400 mum slices. Slices were then incubated for 0.5 h at 32 degrees C in a buffered artificial cerebrospinal fluid (ACSF) bubbled with 95% O2, 5% CO2. Slices were then removed into buffered ACSF containing protease (0.5 mg/ml) at 32 degrees C. After 30 min of enzyme digestion, tissue was rinsed three times in the buffered saline. Then the enzyme-treated slices were mechanically dissociated with a graded series of fire-polished Pasteur pipettes. The cell suspension was then plated into a 35 mm dish and placed on the stage of a Olympus inverted microscope. For whole-cell recordings of currents, standard voltage-clamp techniques were used. Neurons were held at -80 mV, and the I(K) was evoked by 2 000 ms depolarizing voltage commands to potential between -40 mV and +60 mV in 10 mV steps applied at a frequency of 0.5 Hz. It was found that the inhibitory effect of ACh (0.1, 1, 10, 100 mumol/L) on I(K) was dose-dependent. It was also found that ACh affected the activation process of I(K) significantly, i.e., the activation curve of I(K) was characterized by half-activation potential of (-41.8+/-9.7) mV and a slope factor of (30.7+/-7.2) mV in the cortical neurons and they were changed to (-122.4+/-38.6) mV and (42.4+/-7.0) mV, respectively, after giving ACh (10 mumol/L). Tubocurarine (100 mumol/L) antagonized the inhibitory effect of ACh on I(K), and the drop of currents varied from the control value of (36.5+/-7..8)% to (16.9+/-13.8)% (n=8, P<0.01). 4-DAMP (10 mumol/L) blocked the inhibitory effect of ACh on I(K), and the currents reduced from the control value of (36.5+/-7.8)% to (26.8+/-4.7) % (n=6, P<0.05). Pirenzepin did not antagonize the inhibition of ACh on I(K) (n=7, P>0.05). Chelerythrine (20 mumol/L) blocked the inhibitory effect of ACh on I(K) and the currents reduced from the control value of (36.5+/-7.8)% to (11.7+/-17.3)% (n=6, P<0.05). On the contrary, PDBu (10 mumol/L) strengthened the inhibition of ACh on I(K) and the drop of currents changed from the control value of (36.5+/-7.8)% to (59.2+/-14.0)% (n=5, P<0.05). PDBu abolished the antagonism of chelerythrine on ACh in cortical neurons. It is suggested that the ACh-induced depolarization of neurons in the cortex is attributed to the inhibition of I(K) that is most likely evoked by the activation of nicotinic ACh receptors and muscarinic M3 receptor via protein kinase C (PKC) signal transduction pathway.
Acetylcholine ; physiology ; Animals ; Cell Separation ; Delayed Rectifier Potassium Channels ; antagonists & inhibitors ; Female ; Male ; Neurons ; metabolism ; physiology ; Patch-Clamp Techniques ; Protein Kinase C ; metabolism ; physiology ; Rats ; Rats, Wistar ; Receptor, Muscarinic M3 ; metabolism ; Receptors, Nicotinic ; metabolism ; Signal Transduction ; physiology ; Somatosensory Cortex ; cytology ; physiology

AIMTo explore the effects of M3 receptor on myocyte apoptosis induced by acute myocardial infarction in rats.

METHODSRat model was induced by ligation of the anterior branch of the left coronary artery. All animals were divided into four groups: sham-operated group, occlusion group, choline group (10 mg x kg(-1), iv), and 4DAMP (4-diphenylacetoxy-N-methylpiperidine-methiodide) group (0.12 mg x kg(-1), iv). The serum malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were determined. The infarct size areas on the myocardium were identified by TTC staining. The apoptosis in cardiomyocyte was detected by TUNEL assay and apoptosis-related proteins in Bcl-2 and Fas expression were measured by immunohistochemistry assay.

RESULTSM3 receptor agonist choline reduced serum MDA content and increased SOD activity. The myocardial expression of Bcl-2 was increased, whereas the expression of Fas was decreased by choline. However, blockade of M3 receptor by 4DAMP completely inhibited these effects of choline on cardiac myocytes.

CONCLUSIONActivation of M3 receptor has protective effect on myocyte apoptosis induced by acute myocardial infarction in rat, and this effect might be related to modulating the expression of some immediateearly genes including Bcl-2 and Fas.

Animals ; Apoptosis ; Choline ; pharmacology ; Male ; Malondialdehyde ; blood ; Myocardial Infarction ; metabolism ; pathology ; Myocardium ; pathology ; Myocytes, Cardiac ; metabolism ; pathology ; Piperidines ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Wistar ; Receptor, Muscarinic M3 ; agonists ; antagonists & inhibitors ; Receptors, Tumor Necrosis Factor ; metabolism ; Superoxide Dismutase ; blood ; fas Receptor

OBJECTIVETo investigate the effect of M(5) muscarinic receptor subtype on the locomotor sensitization induced by heroin priming, and it's effect on the FosB expression in the nucleus accumbens (NAc) and the hippocampus in the heroin sensitized rats.

METHODSLocomotor activity was measured every 10 min for 1 h after subcutaneous injection of heroin. FosB expression was assayed by immunohistochemistry, and the antisense oligonucleotides (AS-ONs) targeting M(5) muscarinic receptor was transferred with the lipofectin.

RESULTSMicroinjection of AS-ONs targeting M(5) muscarinic receptor in the ventral tegmental area (VTA) blocked the expression of behavioral sensitization induced by heroin priming in rats. Meanwhile, the expression of FosB-positive neurons in either the NAc or the dentate gyrus (DG) of the hippocampus increased in heroin-induced locomotor sensitized rats. The enhancement of FosB-positive neurons in the NAc or DG could be inhibited by microinjection of M(5) muscarinic receptor AS-ONs into the VTA before the heroin-induced locomotor sensitization was performed. In contrast, microinjection of M(5) muscarinic receptor sense oligonucleotide (S-ONs) into the VTA did not block the expression of behavioral sensitization or the expression of FosB in the NAc or DG in the heroin sensitized rats.

CONCLUSIONBlocking M(5) muscarinic receptor in the VTA inhibits the expression of heroin-induced locomotor sensitization, which is associated with the regulation of FosB expression in the NAc and hippocampus neurons. M(5) muscarinic receptor may be a useful pharmacological target for the treatment of heroin addiction.

Acetylcholine ; metabolism ; Animals ; Brain ; drug effects ; metabolism ; physiopathology ; Heroin ; adverse effects ; Heroin Dependence ; drug therapy ; metabolism ; physiopathology ; Hippocampus ; drug effects ; metabolism ; Immunohistochemistry ; Male ; Microinjections ; Motor Activity ; drug effects ; physiology ; Narcotics ; adverse effects ; Neural Pathways ; drug effects ; metabolism ; physiopathology ; Neurons ; drug effects ; metabolism ; Nucleus Accumbens ; drug effects ; metabolism ; physiopathology ; Oligonucleotides, Antisense ; pharmacology ; Proto-Oncogene Proteins c-fos ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor, Muscarinic M5 ; antagonists & inhibitors ; genetics ; metabolism ; Synaptic Transmission ; drug effects ; physiology ; Ventral Tegmental Area ; drug effects ; metabolism ; physiopathology