BACKGROUND: Purinergic and cholinergic agonists elicit negative-inotropic and chronotropic effects, anticip-ating their protective action from the damage of overloaded myocardium. However, the actions of the agents during the ischemic insults are not yet clearly informed. The aim of this study was to investigate the role of the purinergic and cholinergic agonists on the simulated ischemic myocardium of the rat atrial fiber preparations. METHOD: Various action potential parameters (maximum diastolic potential MDP;action potential amplitude APA;velocity of phase 0 depolarization dV/dtmax;action potential duration APD90) were measured and compared in electrically paced, normal (NPSS) and modified physiological salt solution (MPSS) superfused rat atrial fibers in vitro, using conventional 3M-KCl microelectrode technique. Ischemia-simulated modified physiologic solutions were prepared by changing the solution's composition. RESULTS: Hypoxic-and/or hyperkalemic-MPSS decreased all the action potential (AP) variables. However, no significant changes of the AP variables were developed by the acidic-or glucose-free MPSS. Adenosine (Ado) and cyclopentyladenosine (CPA) only decreased the APD90 in a dose-dependent manner. Acetylcholine (Ach) and carbachol (Cch) hyperpolarized the MDP, increased the dV/dtmax with certain doses, and decreased the APD90 dose-depen-dently. The potency for APD90-decrease was greater in order, CPA>Cch>Ach>Ado. Ado and CPA did not affect the hypoxic, hypokalemic MPSS-induced dV/dtmax-decrease. On the other hand, Ach and Cch sig-nificantly inhibited the dV/dtmax-decrease by the hypoxic hypokalemic-MPSS. Ado, CPA, Ach and Cch sig-nificantly augmented the hypoxic, hypokalemic MPSS-induced APD90-decrease. The inhibition by the Ach and Cch on the MPSS-induced dV/dtmax-decrease was not affected by DPCPX, but atropine significantly attenuated the inhibition by the cholinergic agonists. DPCPX inhibited the augmentation by the Ado and CPA on the MPSS induced APD90-decrease, and atropine inhibited the effect of the cholinergic agonists. CONCLUSION: Both purinergic and cholinergic agonists not only shorten the AP duration by themselves but also enhance the AP-shortening effect elicited by the ischemia, and therefore, it is inferred that both agonists prevent further tissue damage from the ischemic insults.
Acetylcholine ; Action Potentials ; Adenosine ; Animals ; Atropine ; Carbachol ; Cholinergic Agonists* ; Hand ; Ischemia ; Microelectrodes ; Myocardium* ; Rats*

OBJECTIVE : We investigated the relationship between the severity of the disease and the abnormality of some ocular movements in parkinson's disease. BACKGROUND: Disorders of eye movements have been described in diseases of the basal ganglia for over a century and ocular motor deficits of the saccadic and pursuit system have been reported in parkinsonian patients. METHOD : We studied the electro-oculography of the eye tracking and saccadic movement in 26 patients (11 males, 15 females) with Parkinson's disease. The severity of the disease was divided into two groups by Hoehn & Yahr(H-Y) staging, H-Y stage 1, 2(group A) and H-Y stage 3, 4 (Group B). Some patients antiparkinsonian drugs of L-dopa, dopamine agonist and anticholinergics. RESULT : The velocity of smooth pursuit and the velocity and latency of saccade were calculated and compared between two groups. Eye tracking test revealed decreased pursuit velocity leading to catch-up saccades, but normal phase relationship between eye and target movement, while saccadic eye movement had increased latency. These results showed more profound severity in more advanced stages of the disease. CONCLUSION : We suggest that ocular movement be often chosen as a simple but relevant example of general motor function, as well as criteria for staging of Parkinson's disease and basal ganglia play significant role in ocular movement.
Basal Ganglia ; Cholinergic Antagonists ; Dopamine Agonists ; Eye Movements ; Humans ; Levodopa ; Male ; Parkinson Disease* ; Pursuit, Smooth ; Saccades

Bethanechol, a cholinergic agonist, has been recommended for the management of peripheral anticholinergic side effects during the treatment of antipsychotic medications. But there have been few studies which have evaluated the drug interactions of antipsychotics and bethanechol, even the treatment effects of bethanechol on anticholinergic side effects. So the authors have evaluated whether psychopathology and plasma haloperidol and reduced haloperidol concentrations are significantly changed or not when bethanechol was administrated with maintained doses of haloperidol and other coadministrated drugs(such a benztropine). Also we have evaluated the abating effects of bethanechol on anticholinergic side effects during the treatment with haloperidol. Fifteen schizophrenics with higher than 5 of total score of anticholinergic side effects of 'Rating scale for side effect' were assigned to two groups, and bethanechol 30mg/day and 60mg/day were applied on each group for 4 weeks. The daily haloperidol dosages were fixed before 2 weeks of study. We assessed anticholinergic side effects by 'Rating scale for side effect' and psychopathology by BPRS, and plasma haloperidol and reduced haloperidol concentrations by HPLC at baseline, 2nd week and 4th week. The results were as followed. 1) There was no significant change of plasma haloperidol and reduced haloperidol concentration. 2) At baseline, the dosage of haloperidol showed significant correlation with the total score of anticholinergic side effect, but not at 2nd week and 4th week. 3) In 60mg/day group, dry mouth and the total score of anticholinergic side effects were significantly improved, but not in 30mg/day group. 4) There was no significant change of BPRS except withdrawal at 2nd week. These results suggest that coadministration of bethanechol influenced neither on psychopathology nor on plasma haloperidol and reduced haloperidol concentrations and that improved dry mouth and total score of anticholinergic side effects at 60mg/day.
Antipsychotic Agents ; Bethanechol* ; Cholinergic Agonists ; Chromatography, High Pressure Liquid ; Drug Interactions ; Haloperidol* ; Mouth ; Plasma* ; Psychopathology ; Schizophrenia

The relationship between M3 cholinergic receptor agonist (carbachol) hyperstimulation-induced pancreatic acinar cellular injury and trypsinogen activation or NF-kappaB activation in rats was studied in vitro. Rat pancreatic acinar cells were isolated, cultured and treated with carbachol, the active protease inhibitor (pefabloc), and NF-kappaB inhibitor (PDTC) in vitro. Intracellular trypsin activity was measured by using a fluorogenic substrate. The cellular injury was evaluated by measuring the leakage of LDH from pancreatic acinar cells. The results showed that as compared with control group, 10(-3) mol/L carbachol induced a significant increase of the intracellular trypsin activity and the leakage of LDH from pancreatic acinar cells. Pretreatment with 2 mmol/L pefabloc could significantly decrease the activity of trypsin and the leakage of LDH from pancreatic acinar cells (P < 0.01) following the treatment with a high concentration of carbachol (10(-3) mol/L) in vitro. The addition of 10(-2) mol/L PDTC didn't result in a significant decrease in the activity of trypsin and the leakage of LDH from pancreatic acinar cells treated with a high concentration of carbachol (10(-3) mol/L) in vitro (P > 0.05). It was concluded that intracellular trypsinogen activation is likely involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro. NF-kappaB activation may not be involved in pancreatic acinar cellular injury induced by carbachol hyperstimulation in vitro.
Carbachol/*pharmacology ; Cholinergic Agonists/pharmacology ; NF-kappa B/*metabolism ; Pancreas/metabolism ; Pancreas/*pathology ; Rats, Wistar ; Receptor, Muscarinic M3/agonists ; Trypsinogen/*metabolism

BACKGROUND/AIMS: Gastric peristalsis begins in the orad corpus and propagates to the pylorus. Directionality of peristalsis depends upon orderly generation and propagation of electrical slow waves and a frequency gradient between proximal and distal pacemakers. We sought to understand how chronotropic agonists affect coupling between corpus and antrum. METHODS: Electrophysiological and imaging techniques were used to investigate regulation of gastric slow wave frequency by muscarinic agonists in mice. We also investigated the expression and role of cholinesterases in regulating slow wave frequency and motor patterns in the stomach. RESULTS: Both acetycholinesterase (Ache) and butyrylcholine esterase (Bche) are expressed in gastric muscles and AChE is localized to varicose processes of motor neurons. Inhibition of AChE in the absence of stimulation increased slow wave frequency in corpus and throughout muscle strips containing corpus and antrum. CCh caused depolarization and increased slow wave frequency. Stimulation of cholinergic neurons increased slow wave frequency but did not cause depolarization. Neostigmine (1 muM) increased slow wave frequency, but uncoupling between corpus and antrum was not detected. Motility mapping of contractile activity in gastric muscles showed similar effects of enteric nerve stimulation on the frequency and propagation of slow waves, but neostigmine (> 1 muM) caused aberrant contractile frequency and propagation and ectopic pacemaking. CONCLUSIONS: Our data show that slow wave uncoupling is difficult to assess with electrical recording from a single or double sites and suggest that efficient metabolism of ACh released from motor neurons is an extremely important regulator of slow wave frequency and propagation and gastric motility patterns.
Animals ; Cholinergic Neurons ; Cholinesterases* ; Metabolism ; Mice* ; Motor Neurons ; Muscarinic Agonists ; Muscle, Smooth ; Muscles ; Neostigmine ; Peristalsis ; Pylorus ; Stomach

Parkinson's disease is one of the most common neurodegenerative disorders world widely. Although curable therapies are practically not available yet, symptomatic managements using anti-Parkinson medications have shown to be quite effective to improve patients' quality of life. The discovery of dopaminergic deficits in Parkinson's disease in 1960s have brought about the human clinical trials of levodopa, which opened an “Era of Dopamine” in treatment history of the Parkinson's disease. Levodopa still remains gold standard. Dopamine agonists have proved their efficacies and delayed the development of long-term complications of levodopa use. Inhibitors of respective enzyme monoamine oxidase-B and catechol-O-methyltransferase, anticholinergics, and amantadine strengthen the therapeutic effects via either monotherapy or adjunctive way. Strategy of continuous dopaminergic stimulation and disease modification are weighing in current advances. This article is providing evidence-based review of pharmacological treatment of Parkinson's disease from early to advanced stages as well as management its unavoidable adverse reactions.
Amantadine ; Catechol O-Methyltransferase ; Cholinergic Antagonists ; Dopamine Agonists ; Drug Therapy ; Humans ; Levodopa ; Neurodegenerative Diseases ; Parkinson Disease ; Quality of Life ; Therapeutic Uses

Aim of this study was to investigate if pancreatic polypeptide (PP) reduced the insulin action via the intra-pancreatic cholinergic nerves in the isolated rat pancreas. The pancreas was isolated from rats and perfused with intra-arterial infusion of modified Krebs-Henseleit solution containing 2.5 mM glucose at a flow rate of 1.2 ml/min. Simultaneous intra-arterial infusion of insulin (100 nM) resulted in potentiation of the pancreatic flow rate and amylase output which were stimulated by cholecystokinin (CCK, 14 pM). These potentiating actions of insulin on the CCK-stimulated pancreatic exocrine secretion were completely abolished by administration of rat PP. Vesamicol, a potent inhibitor of vesicular acetylcholine storage, and tetrodotoxin (TTX) also significantly reduced the combined actions of insulin and CCK. Administration of carbamylcholine, an acetylcholine agonist, completely restored the vesamicol-or TTX-induced inhibition of the potentiation between insulin and CCK. Also rat PP failed to attenuate the restoring effect of carbamylcholine. Electrical field stimulation (15-30 V, 2 msec and 8 Hz) resulted in a significant increase in the pancreatic flow rate and amylase output in voltage-dependent manner. Effects of electrical field stimulation were augmented by endogenous insulin. Rat PP also suppressed the pancreatic exocrine secretion stimulated by electrical field stimulation. These observations strongly suggest that PP inhibits the potentiating actions of insulin on CCK-stimulated pancreatic exocrine secretion by suppression of the intra-pancreatic cholinergic activity in the isolated rat pancreas.
Acetylcholine ; Amylases ; Animals ; Carbachol ; Cholecystokinin ; Cholinergic Agonists ; Glucose ; Infusions, Intra-Arterial ; Insulin ; Pancreas* ; Pancreatic Polypeptide* ; Rats* ; Tetrodotoxin

Acetylcholine ; metabolism ; physiology ; Animals ; Cholinergic Agonists ; pharmacology ; Male ; Muscle Contraction ; drug effects ; physiology ; Muscle Relaxation ; drug effects ; physiology ; Muscle, Smooth ; drug effects ; pathology ; physiopathology ; Rabbits ; Random Allocation ; Receptors, Cholinergic ; physiology ; Synaptic Transmission ; drug effects ; Urinary Bladder ; drug effects ; innervation ; physiopathology

To investigate the mechanisms underlying the cholinergic agonist carbachol-induced cardiovascular responses, changes of renin-angiotensin system were examined in fetal hormonal systems. In the ovine fetal model under stressless condition, the cardiovascular function was recorded. Blood samples were collected before (during baseline period) and after the intravenous administration of carbachol. Simultaneously, the levels of angiotensin I (Ang I), angiotensin II (Ang II) and vasopressin in the fetal plasma were detected by immunoradiological method. Also, blood gas, plasma osmolality and electrolyte concentrations were analyzed in blood samples. Results showed that in chronically prepared ovine fetus, intravenous infusion of carbachol led to a significant decrease of heart rate (P < 0.05), and a transient decrease followed by an increase of blood pressure (P < 0.05) within 30 min. After the intravenous infusion of carbachol, blood concentrations of Ang I and Ang II in near-term ovine fetus were both significantly increased (P < 0.05); however, blood concentration of vasopressin, values of blood gas, electrolytes and plasma osmolality in near-term ovine fetus were not significantly changed (P > 0.05). Blood levels of Ang I and Ang II in the atropine (M receptor antagonist) + carbachol intravenous administration group was lower than those in the carbachol group without atropine administration (P < 0.05). In conclusion, this study indicates that the near-term changes of cardiovascular system induced by intravenous administration of carbachol in ovine fetus, such as blood pressure and heart rate, are associated with the changes of hormones of circulatory renin-angiotensin system.
Angiotensin I ; blood ; Angiotensin II ; blood ; Animals ; Blood Pressure ; Carbachol ; pharmacology ; Cholinergic Agonists ; pharmacology ; Fetus ; Heart Rate ; Renin-Angiotensin System ; Sheep ; Vasopressins ; blood

Animals ; Arecoline ; pharmacology ; Cholinergic Agonists ; pharmacology ; Female ; Guinea Pigs ; In Vitro Techniques ; Male ; Muscle Contraction ; drug effects ; Muscle, Smooth ; physiology ; Pyloric Antrum ; physiology ; Receptor, Muscarinic M3 ; metabolism