Metabolic and vascular pattern in medial pterygoid muscle is altered by chronic stress in an animal model of hypodontia

Author(s)

Restrepo Fernandez, Rodrigo Alberto ^[1] ; Lara Pereira, Yamba Carla ^[2] ; Iyomasa, Daniela Mizusaki ^[1] ; Calzzani, Ricardo Alexandre ^[1] ; Andrade Leite-Panissi, Christie Ramos ^{[3, 1]} ; Iyomasa, Mamie Mizusaki ^[1] ; Nascimento, Glauce Crivelaro ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Dent Fac, Dept Morphol Physiol & Basic Pathol, BR-14040904 Ribeirao Preto, SP - Brazil

^[2] Univ Estadual Campinas, Sch Dent Piracicaba, Biol Dent Buco Grad Program, BR-13414903 Piracicaba, SP - Brazil

^[3] Univ Sao Paulo, Sch Philosophy Sci & Literature Ribeirao Preto, Psychobiol Grad Program, BR-14040901 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Physiology & Behavior; v. 185, p. 70-78, MAR 1 2018.
• Web of Science Citations: 0

Abstract

Psychological stress is an important perpetuating, worsening and risk factor for temporomandibular disorders of muscular or articular origin. Occlusion instability, by the way, is considered a risk factor of this pathology and can be reproduced in some experimental animal models. The exact physiologic mechanism underlying, these relations however, remains unclear. Our purpose was to test the hypothesis that chronic stress and unilateral exodontia induce metabolic and vascular changes in the medial pterygoid muscle of rats. Adult Wistar rats were submitted to chronic unpredictable stress and/or unilateral exodontia and their plasma and medial pterygoid muscle were removed for analysis. The parameters evaluated included plasma levels of corticosterone, metabolic activity by succinate dehydrogenase, oxidative capacity by nicotinamide adenine dinucleotide diaphorase, capillary density by laminin and alfa-CD staining and reactive oxidative species production. Chronic unpredictable stress as an isolated factor, increased oxidative metabolism, capillary density and reactive oxygen species production at medial pterygoid muscle. Conversely, exodontia has a main effect in metabolism, promoting glycolytic transformation of muscle fibers. Association of both factors induced a major glycolytic pattern in muscle and vascular changes. Our findings provide insights into the mechanisms, possibly inducing metabolic and vascular alterations on medial pterygoid muscle of rats, by which chronic stress and occlusal instabilities might be involved as risk factors in the pathophysiology of temporomandibular disorders with muscular components. (AU)

• FAPESP's process: 12/22128-6 - Effects of systemic stress associated with malocclusion medial pterygoid muscle and the brain
• Grantee: Mamie Mizusaki Iyomasa
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/03053-3 - Evaluation of medial pterygoid muscle and brain structures related to orofacial nociception and emotional behavior in an animal model of chronic stress and masticatory hypofunction
• Grantee: Glauce Crivelaro Do Nascimento
• Support Opportunities: Scholarships in Brazil - Post-Doctoral