Age-related decrease of cholinergic parasympathetic reflex vasodilation in the rat masseter muscle
Autor: | Ratna Ramadhani, Tetsuro Saito, Yuri Hirohata, Toshiya Sato, Kohei Mito, Hisayoshi Ishii, Rina Ishikawa, Yunosuke Okada |
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Rok vydání: | 2021 |
Předmět: |
Male
medicine.medical_specialty Aging Vasodilation Vagotomy Biochemistry Masseter muscle chemistry.chemical_compound Parasympathetic Nervous System Internal medicine Muscarinic acetylcholine receptor Reflex medicine Animals Trigeminal Nerve Rats Wistar Sympathectomy Receptor Muscarinic M3 business.industry Masseter Muscle Receptor Muscarinic M1 Age Factors Skeletal muscle Cell Biology Arteries Acetylcholine Electric Stimulation Atropine Endocrinology medicine.anatomical_structure chemistry Cholinergic Fibers Regional Blood Flow Cholinergic Hexamethonium Cardiology and Cardiovascular Medicine business circulatory and respiratory physiology medicine.drug |
Zdroj: | Microvascular research. 138 |
ISSN: | 1095-9319 |
Popis: | Skeletal muscle hemodynamics, including that in jaw muscles, is an important in their functions and is modulated by aging. Marked blood flow increases mediated by parasympathetic vasodilation may be important for blood flow in the masseter muscle (MBF); however, the relationship between parasympathetic vasodilation and aging is unclear. We examined the effect of aging on parasympathetic vasodilation evoked by trigeminal afferent inputs and their mechanisms by investigating the MBF during stimulation of the lingual nerve (LN) in young and old urethane-anesthetized and vago-sympathectomized rats. Electrical stimulation of the central cut end of the LN elicited intensity- and frequency-dependent increases in MBF in young rats, while these increases were significantly reduced in old rats. Increases in the MBF evoked by LN stimulation in the young rats were greatly reduced by hexamethonium and atropine administration. Increases in MBF in young rats were produced by exogenous acetylcholine in a dose-dependent manner, whereas acetylcholine did not influence the MBF in old rats. Significant levels of muscarinic acetylcholine receptor type 1 (MR1) and type 3 (MR3) mRNA were observed in the masseter muscle in young rats, but not in old rats. Our results indicate that cholinergic parasympathetic reflex vasodilation evoked by trigeminal afferent inputs to the masseter muscle is reduced by aging and that this reduction may be mediated by suppression of the expression of MR1 and MR3 in the masseter muscle with age. |
Databáze: | OpenAIRE |
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