Journal: Cerebellum (London, England)

Article Title: Projections from Regions of the Cerebellar Nuclei Receiving Jaw Muscle Proprioceptive Signals to Trigeminal Motoneurons and Their Premotoneurons in the Rat Pons and Medulla

doi: 10.1007/s12311-025-01862-7

Figure Lengend Snippet: Electrophysiologically evoked responses recorded in the dorsolateral hump of the interposed cerebellar nucleus (IntDL) ( a– f ) and the dorsolateral protuberance of the medial cerebellar nucleus (MedDL) ( i– l ) of the cerebellar nuclei on the right side ipsilateral to the electrically stimulated masseter nerve and injection sites of anterograde tracer biotinylated dextran amine (BDA) made at the recording sites ( g , h , m , n ). a , c , e , i , k Field potentials evoked by electrical stimulation of the ipsilateral masseter nerve. Arrowheads indicate peak responses with approximate latencies of 2.7 ms ( a ), 2.8 ms ( c ), 2.9 ms ( e ), 2.4 ms ( i ) and 2.7 ms ( k ). b , d , f, j, l Extracellular multi-unit discharges recorded during a sustained jaw-opening (stretching the muscle spindles of the jaw-closing (JC) muscles [JCMSs]). Horizontal lines in panels b , d , f, j, l indicate durations of jaw-opening (approximately 5.5 s, 6.5 s, 5.0 s, 4.5 s and 4.8 s, respectively). Note that each recording site corresponds to the center of BDA-deposit that was subsequently injected. g , m Drawings of coronal sections including the cerebellar nuclei. In rat R307, both responses a and b were recorded at the site indicated by a red dot in the IntDL in panel g . The extent of the BDA-deposit in this rat is indicated by a red circle in panel g and is shown in photomicrograph h . The boxed area in panel g corresponds to the area shown in photomicrograph h . In rat R112, both responses c and d were recorded at the site indicated by a green dot in the IntDL in panel g . In rat R506, both responses e and f were recorded at the site indicated by a sky-blue dot in the IntDL in panel g . In rat R126, both responses i and j were recorded at the site indicated by a blue dot in the MedDL in panel m . The extent of the BDA-deposit in this rat is indicated by a blue circle in panel m and is shown in photomicrograph n . The boxed area in panel m corresponds to the area shown in photomicrograph n . In rat R101, both responses k and l were recorded at the site indicated by a green dot in the MedDL in panel m . In panels g and m , recording sites (the centers of BDA deposits) where both types of responses described above were recorded are labeled as “Stim resp + Passive resp” and indicated by colored dots. Sites where only the extracellular multi-unit discharges during sustained jaw-opening were recorded are labeled as “Passive resp only” and indicated by filled triangles. For abbreviations, see the abbreviations list. Scale bars = 1 ms and 0.2 mV in ( a ), ( c ) and ( i ) as in ( e ) and ( k ); 0.4 mV in ( b ), ( d ) and ( j ) as in ( f ) and ( l ); 0.5 mm in ( g ) and ( h ) as in ( m ) and ( n )

Article Snippet: We vertically inserted a glass electrode filled with an anterograde tracer biotinylated dextran amine (BDA; 4%; 10,000 MW; Molecular Probes, Eugene, OR, USA) dissolved in 0.01 M phosphate buffer (PB; pH 7.4) into the right cerebellum to target the jcms-IntDL or jcms-MedDL, as previously described [ ].

Techniques: Injection, Muscles, Labeling