title: Possible neural network mediating jaw opening during prey-catching behavior of the frog.
abstract: The prey-catching behavior of the frog is a complex, well-timed sequence of stimulus response chain of movements. After visual analysis of the prey, a size dependent program is selected in the motor pattern generator of the brainstem. Besides this predetermined feeding program, various direct and indirect sensory inputs provide flexible adjustment for the optimal contraction of the executive muscles. The aim of the present study was to investigate whether trigeminal primary afferents establish direct contacts with the jaw opening motoneurons innervated by the facial nerve. The experiments were carried out on Rana esculenta (Pelophylax esculentus), where the trigeminal and facial nerves were labeled simultaneously with different fluorescent dyes. Using a confocal laser scanning microscope, close appositions were detected between trigeminal afferent fibers and somatodendritic components of the facial motoneurons. Quantitative analysis revealed that the majority of close contacts were encountered on the dendrites of facial motoneurons and approximately 10% of them were located on the perikarya. We suggest that the identified contacts between the trigeminal afferents and facial motoneurons presented here may be one of the morphological substrate in the feedback and feedforward modulation of the rapidly changing activity of the jaw opening muscle during the prey-catching behavior.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Kovalecz
authors.affiliation: Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary.
authors.forename: Szilvia
authors.initials: S
authors.lastname: Kecskes
authors.affiliation: Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Birinyi
authors.affiliation: Department of Anatomy, Histology and Embryology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary; MTA-DE Neuroscience Research Group, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary; Division of Oral Anatomy, Faculty of Dentistry, University of Debrecen, Nagyerdei krt. 98, Debrecen H-4032, Hungary. Electronic address: matesz@anat.med.unideb.hu.
authors.forename: Clara
authors.initials: C
authors.lastname: Matesz
mesh_terms: D000344:Afferent Pathways / Q000166:cytology / Q000502:physiology; D000818:Animals; D003712:Dendrites; D005154:Facial Nerve / Q000166:cytology* / Q000502:physiology; D007568:Jaw / Q000033:anatomy & histology / Q000502:physiology; D018613:Microscopy, Confocal; D009046:Motor Neurons / Q000166:cytology* / Q000502:physiology; D009475:Neurons, Afferent / Q000166:cytology* / Q000502:physiology; D010784:Photomicrography; D011235:Predatory Behavior / Q000502:physiology*; D011893:Rana esculenta / Q000033:anatomy & histology* / Q000502:physiology; D014278:Trigeminal Nuclei / Q000166:cytology* / Q000502:physiology
keywords: Brainstem; Neurolucida reconstruction; Neuronal labeling; Nucleus nervi facialis