title: Ovalbumin-induced sensitization affects non-quantal acetylcholine release from motor nerve terminals and alters contractility of skeletal muscles in mice.
abstract: Skeletal muscles play key roles in the development of various pathologies, including bronchial asthma and several types of auto-immune disorders, e.g. polymyositis. Since most of these maladies have an immunological/allergic element, this paper is devoted to assessing the impact of immunobiological reorganization on the functional properties of isolated skeletal muscles in mice. A combination of two methods (myography and electrophysiology) was used to evaluate extensor digitorum longus (EDL) and diaphragmatic muscle (DM) in this regard. Conventional myographic technique showed that ovalbumin-induced sensitization (OS) produced different changes in the contractile properties of EDL and DM. The amplitudes of carbachol (CCh)-induced contractions increased in DM but decreased in EDL. Those changes were inversely related to OS-mediated changes of non-quantal acetylcholine (ACh) release intensity within the muscle endplate, as shown by the electrophysiologically measured H-effect. These results clearly show that OS-mediated changes of non-quantal ACh release alter the functional properties of postjunctional ACh receptors and therefore contribute to the disturbance of CCh-induced contractility of skeletal muscles. Other mechanisms of OS-mediated changes of skeletal muscle contractility are also proposed and discussed.
authors.affiliation: Department of Pathophysiology, Kazan State Medical University, Russia.
authors.forename: Alexander Y
authors.initials: AY
authors.lastname: Teplov
authors.forename: Sergey N
authors.initials: SN
authors.lastname: Grishin
authors.forename: Marat A
authors.initials: MA
authors.lastname: Mukhamedyarov
authors.forename: Airat U
authors.initials: AU
authors.lastname: Ziganshin
authors.forename: Andrey L
authors.initials: AL
authors.lastname: Zefirov
authors.forename: András
authors.initials: A
authors.lastname: Palotás
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D018679:Cholinergic Agonists / Q000494:pharmacology; D004195:Disease Models, Animal; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006967:Hypersensitivity / Q000378:metabolism / Q000503:physiopathology; D007114:Immunization / Q000379:methods*; D008297:Male; D051379:Mice; D009046:Motor Neurons / Q000378:metabolism*; D009119:Muscle Contraction / Q000187:drug effects* / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects / Q000502:physiology*; D009213:Myography / Q000379:methods; D009469:Neuromuscular Junction / Q000378:metabolism / Q000503:physiopathology; D010047:Ovalbumin / Q000009:adverse effects / Q000494:pharmacology*; D017729:Presynaptic Terminals / Q000378:metabolism*
chemical_list: D018679:Cholinergic Agonists; D002217:Carbachol; D010047:Ovalbumin; D000109:Acetylcholine