role of botulinum toxin a in treatment of temporomandibular joint disorders: a review

Temporomandibular joint disorders [TMDs] usually present with symptoms and signs such as pain, mandibular movement, dysfunction, or joint sounds. Botulinum toxin type A [BTX-A] is a biologic toxin which inhibits skeletal muscle through hindering the production of acetylcholine in the nerve endings. This toxin is used for the treatment of hyperactivity of lateral pterygoid muscle and TMD symptoms. This comprehensive review aimed to evaluate the effect of BTX-A injections in the lateral pterygoid muscle on treatment of TMDs symptoms.In this study, online databases including Scopus, Medline, Ebsco, Cochrane, EMBASE, and Google scholar were searched for the keywords [pterygoid muscle] and [Onabotulinumtoxin A]

Twenty-four articles were eligible to be enrolled in the study. In 4 interventional studies and 20 descriptive studies, BTX-A was used for the treatment of TMDs. The dosage and number of injections were different in each study; however, the injection methods were relatively similar. Regardless of the type, number of injections, and dosage, injection of BTX-A in lateral pterygoid seems effective in reducing the click sound and other TMJ-related muscle disorders such as pain, hyperactivity, and dysfunction

p-Coumaric acid reduces high glucose-mediated impairment of endothelium-dependent relaxation in rat aorta / Ácido p-cumárico reduce el deterioro mediado por alta glucosa de la relajación dependiente de endotelio en aorta de rata

p-Coumaric acid (p-CA) is an ubiquitous plant metabolite with antioxidant, anti-inflammatory, and anticancer properties. The present study was designed to evaluate the preventive effects of p-CA on endothelium-dependent impairment produced by high glucose (HG) (D-Glucose 25 mM) in isolated rat thoracic aorta. Aortic rings obtained from male Sprague-Dawley rats were mounted in an organ bath and pretreated for 3 h with D-Glucose 5 mM, HG and HG plus p-CA (1, 10 and 100 uM). After this period of time endothelium-dependent relaxation was tested by cumulative addition of acetylcholine (ACh) in pre-contracted rings with phenylephrine (PE) (0.1 μM). p-CA elicited a moderate endothelium-dependent vasodilatory effect (Emax= 29.28 +/- 1.89 percent, N=6; pD2= 6.075 +/- 0.184, N=6). When aortic rings were pre-incubated for 3 h with HG, Emax for ACh decreased dramatically from 87.69 +/- 2.59 percent (N=6) to 40.54 +/- 1.78 percent (N=6). The negative effect of HG was partially reverted in rings co-incubated with p-CA in a concentration-dependent manner as shown for Emax values to each p-CA concentration: 1 uM (48.57 +/- 1.82 percent), 10 uM (60.81 +/- 1.80 percent) and 100 uM (64.51 +/- 1.80 percent). The action of p-CA was associated with a significant change in Emax. No statistical difference in pD2 was observed. Our results clearly show that p-CA protect ACh-induced endothelial-dependent relaxation affected by HG in isolated rat aortic rings.

El ácido p-cumárico (p-CA) es un metabolito ubicuo en plantas, con propiedades antioxidantes, anti-inflamatoria, y anticancerígenas. El presente estudio fue diseñado para evaluar los efectos preventivos de p-CA sobre la relajación dependiente de endotelio, deteriorada por niveles altos de glucosa (HG) (D-glucosa 25 mM) en aorta torácica aislada de rata. Los anillos aórticos obtenidos de ratas macho Sprague-Dawley se montaron en un baño de órganos y fueron pre-tratados durante 3 h con D-glucosa 5 mM, HG, y HG más de p-CA (1, 10 y 100 uM). Después de este período de tiempo se evaluó la relajación dependiente de endotelio mediante la adición acumulativa de acetilcolina (ACh) en anillos pre-contraídos con fenilefrina (PE) (0,1 uM). p-CA mostró un moderado efecto vasodilatador dependiente de endotelio (Emax = 29,28 +/- 1,89 por ciento, N = 6; pD2 = 6,075 +/- 0,184, N = 6). Cuando los anillos aórticos se pre-incubaron durante 3 h con HG, la Emax para ACh se redujo drásticamente desde 87,69 +/- 2,59 por ciento (N = 6) a 40,54 +/- 1,78 por ciento (N = 6). El efecto negativo de HG se revirtió parcialmente, de manera dependiente de concentración, en los anillos co-incubados con p-CA tal como lo muestra el valor de Emax para cada concentración de p-CA: 1 u M (48,57 +/- 1,82 por ciento), 10 uM (60,81 +/- 1,80 por ciento) y 100 uM (64,51 +/- 1,80 por ciento). La acción de p-CA se asoció con un cambio significativo en la Emax. No se observó diferencia estadísticamente significativa en el pD2. Nuestros resultados muestran claramente que p-CA protege la relajación dependiente de endotelio inducida por ACh, la cual es afectada por HG en anillos aislados de aorta de rata.

A Case of Combined Cholinergic and Cold Urticaria

No abstract available.

Neurotransmitter release in aggregate cultures of chick embryo retina cells

The study of neurotransmitter release using aggregate cell cultures has been limited by the fact that cell aggregates are obtained only when cells are maintained in suspension with rotatory agitation. In this report we describe a simple and easy method that uses aggregate cell cultures to study the release of neurotransmitters. The results demonstrate that this relatively simple technique can be of great value to address the problem of neurotransmitter release and study the mechanisms of action of natural and synthetic compounds on the differentiation of functional synapses in the CNS.

Monoamines and acetylcholine in primate cerebral cortex: what anatomy tells us about function

In primates, cholinergic and monoaminergic axons that innervate the cerebral cortex originate almost exclusively from subcortical nuclei in the brainstem and basal forebrain. These projections are thought to modulate cortical activity during arousal, attention and memory formation. Physiological and anatomical evaluations of these ascending projections suggest that they have overlapping but somewhat distinctive synaptic targets in the cortex. This review compares the anatomical organization of acetylcholine-, dopamine-, norepinephrine-, and serotonin-containing axon systems in the monkey and human cerebral cortex. Analysis of the distributions of axons, receptors, and synapses suggests that each system in likely to have a differential role in modulating cortical function.

Effect of felodipine on cholinergic responses of the colonic smooth muscle of streptozotocin induced diabetic rats.

In streptozotocin induced diabetic rats, irrespective of felodipine treatment (5 mg/kg/day po for 4 weeks), a reduction in contractile response of colonic smooth muscle in vitro was observed. Similarly, in both control and diabetic rats treated with felodipine, contractile response was reduced. However, in felodipine treated diabetic rats there was a significant increase in response to exogenous acetylcholine. It may be of interest to study the effect of felodipine, on gastro-intestinal motility in vivo in diabetic rats, to enable extrapolation of the present results to the effect of felodipine on gastrointestinal complications of diabetes mellitus.

The influence of gastrokinetics and inhibitors of acid secretion on motor responses of the gastric fundus to acetylcholine

The influence of eight gastrokinetics and six inhibitors of acid secretion used routinely in gastrointestinal prescriptions were verified, through dose-response curves to acetylcholine, on longitudinal muscular gastric fundus secretions of 70 rats. Some drugs increased the fundic motor response, and few others decreased the affinity of the fundi for acetylcholine. The results of the present paper may contribute to the knowledge of the effect of these drugs on gastric motility

Effect of felodipine on myocardial function and cholinergic responses in short term streptozotocin diabetes in rats.

Cardiovascular complications of diabetes mellitus account for 80% of deaths among diabetics. Autonomic neuropathy increases the susceptibility of the diabetic myocardium to arrhythmias. Decreased contractility of diabetic myocardium is associated with intracellular calcium overload. However, the relationship between calcium levels and myocardial cholinergic responses is not known. This study was undertaken to observe the effect of felodipine 5 mg/kg on myocardial function and cholinergic responses of the spontaneously working isolated heart of rats with short term streptozotocin-diabetes. Felodipine was administered (po) for 4 week to rats with streptozotocin-diabetes of 4 week duration. Felodipine did not alter the blood glucose levels. The increased cardio-somatic ratio in diabetic rats was attenuated by felodipine. Diabetic status was associated with decreased coronary flow and felodipine increased coronary flow in diabetic rat hearts both before and after ACh. It may be concluded that felodipine favourably altered the adverse myocardial pathology in experimental diabetes, and this strengthens its use as an antihypertensive in diabetics.

Oxido nítrico y anestesia / Nitric oxide and anesthesia

La presente revisión, describe las implicaciones fisiológicas, anestésicas y los efectos de óxido nítrico (NO) sobre la ciruclación pulmonar y el síndrome de insuficiencia respiratoria progresiva del adulto. La importancia para el anestesiólogo del óxido nítrico (NO) y/o el efecto de relajación derivado del endotelio, (FRDE)va más alla del entendimiento del papel de este último, en los estados fisiológicos y fisiopatológicos cardiovasculares. ¿Como son medidas estas interacciones? ¿Existen diferencias significativas entre los anestésicos con relación a sus efectos sobre el FRDE? ¿Es clínicamente importante el efecto de los anestésicos en la actividad basal de FRDE o solo en respuesta a una estimulación exógena?. Son preguntas que se plantean durante esta revisión

Inervaçäo autônoma do útero de mamíferos / Autonomic Innervation of the mammalian uterus

Apresenta-se uma revisäo sobre a inervaçäo autônoma do útero de mamíferos.

Effect of alcohols and their potentiating responses on acetylcholine induced contractures on frog rectus abdominis.

Ethanol, propanol and butanol cause contraction and potentiate the responses of acetylcholine (Ach) on frog's rectus muscle. These actions are minimum with ethanol and maximum with butanol. Various drugs acting at different levels of neuromuscular transmission inhibited the responses of alcohol itself and also its potentiating responses of Ach. The results show that these effects are partly due to enhanced release of Ach at neuromuscular junction and partly due to release of sarcoplasmic calcium suggesting that more than one mechanism may be responsible for these actions.

Effects of muscarinic receptor agonists and antagonists on response of non-extensor rats to maximal electroshock.

Rats which do not respond consistently to maximal electroshock by exhibiting the classical hindlimb extensor response, are designated as 'flexors', and can serve as a useful experimental model for investigating seizure mechanisms. 20-25% Charles Foster rats exhibit the flexor status and were used in this study. The flexor rats were converted to extensors by acetylcholine (icv), physostigmine (ip) and the selective muscarinic M1 receptor agonists, arecholine (ip) and McN-A-343 (icv). This conversion of flexors to extensors was significantly attenuated by M1 receptor antagonists scopolamine (ip) and pirenzepine (icv). The M2 receptor agonist, carbachol (icv), had no effect in lower doses but induced conversion of flexor rats to the extensor status only in very high doses which may be due to loss of receptor specificity on dose increment. The M2 receptor antagonists, gallamine (icv) and AF-DX 116 (ip), also induced significant conversion of flexors to extensors, which was dependent upon the availability of neuronal acetylcholine since the effects were attenuated following pretreatment with hemicholinium, an inhibitor of acetylcholine synthesis. The results suggest that the central cholinergic system has a facilitatory pro-convulsant effect, mediated through the muscarinic M1 receptors, an action modulated by the M2 receptors.

Role of acetylcholine and dopamine in dorsal hippocampus on hoarding behavior in rats.

The probable roles of Acetylcholine (Ach) and Dopamine (DA) in the modulation of instinctual behaviors of feeding and hoarding (HS), as also the body weight and vaginal cyclicity (EI), were studied by instillation of Atropine (Ach antagonist), Haloperidol (DA antagonist) and Apomorphine (DA agonist) in the dorsal hippocampus of nonpregnant female rats. It was observed that the HS was significantly decreased with both Atropine and haloperidol and increased with Apomorphine, although the food intake was decreased with the three chemicals. It appears that action of both Ach and DA on the dorsal hippocampus has a positive influence on hoarding behavior.

Resting tension and histopathology of intestinal smooth muscle of chagasic mice

La enfermedad de Chagas experimental se logró inoculando 45 tripomastigotes de T.cruzi cepa Tulahuen por animal (ratones Albinos Suizos de 3 meses de edad). Se estudió el efecto de NE y ACh sobre la tensión de reposo del músculo colónico desde los 2 días a los 180 días posteriores a la inoculación (p.i.). Desde los 2 a los 37 días p.i. el efecto de NE fue significativamente monor que el del grupo control. A partir de los 45 días p.i., no se observaron diferencias significativas con los valores normales. Durante la etapa aguda y hasta los 15 días p.i. las reacciones inflamatorias se caracterizaron por infiltrado de células mononucleares a nivel del plexo mioentérico y la pared intestinal. Fue frecuente la observación de parásitos en el tejido infectado; el efecto de ACh fue significativamente inferior en algunos de los gurpos de la etapa aguda, hecho que se mantuve constante en la etapa indeterminada (p < 0.001), persistiendo hasta los 5 meses p.i. A partir de los 165 días y hasta los 180 días p.i., la respuesta intestinal retornó una restitución "ad integrum" de los tejidos dañados. La respuesta farmacológica descripta en este modelo experimental sugiere que la Tripanosomiasis Americana produce alteraciones a nivel de los receptores muscarínicos únicamente en la etapa aguda e intermedia de la enfermedad de Chagas

Anaphylactic reaction in smooth muscle from the duck

1. Para saber si la falta de desensibilizacón en el pollo es característica del tejido aviario, se estudió la reacción anafiláctica en el pato. Las contracciones provocadas en segmentos de intestino de patos sensibilizados activamente, por exposición al antígeno específico, o reacción de Schultz-Dale, se comparan con respuestas similares de intestino sensibilizado de pollo y de cobayo. 2. El músculo liso de pollo sensibilizado activamente, se contrae cuando se le expone in vitro al antígeno específico. La tensión máxima desarrolalada duratne la reacción anafiláctica, se mantiene hasta que se lava la preparación. Una nueva exposición del músculo al antígeno produce otra vez desarrollo de tensión. Esto significa que la exposición al antígeno no desensibiliza el intestino de pollo. 3. El músculo liso intestinal de patos sensibilizados desarrolló tensión cuando se añadió el antígeno específico al bño, la tensión fué transitoria y pronto alcanzó la línea basal aún antes de lavar el antígeno. A diferencia de las observaciones en el músculo liso del pollo, una segunda dosis de antígeno no produce contracciónd el intestino del pato. El músculo liso del pato se comportó como el tejido del mamífero. La exposición al antígeno desensibilizó el intestino del pato. 4. En el pato con sensibilización múltiple, el orden de administración de los antígenos y su desensibilización no modifican la respuesta anafiláctica a cada antígeno. 5. Estos resultados se discuten en términos de las propiedades conocidas de los anticuerpos del pato

Sinoaortic denervation: serotonergic and cholinergic participation

This review describes the role of serotonergic and cholinergic pathways in blood pressure relagulation after sinoaortic denervation of rats. The changes observed in serotonergic activity were related to the development and/or the maintenance of neurogenic hypertension. The data indicate that baroreceptor deafferentation could affect the peripheral parasympathetic tone which regulates heart rate. Moreover, there is evidence that brain cholinergic neurons may be involved in the process of neurogenic hypertension produced by sinoaortic denervation