Abstract Serotonergic projections from raphe nuclei arrive in the lumbar enlargement of spinal cord during late fetal period rat, a time window which locomotor‐related left/right and flexor/extensor coordinations switch synchrony to alternation. The goal present study was investigate role played by serotonin (5‐HT) modulating alternations. Fictive locomotion induced bath application N ‐methyl‐ d , l ‐aspartate (NMA) vitro neonatal rat preparation. By means cross‐correlation analysis we...

The central pattern generators (CPGs) for locomotion, located in the lumbar spinal cord, are functional at birth rat. Their maturation occurs during last few days preceding birth, a period which first projections from brainstem start to reach enlargement of cord. goal present study was investigate effect suppressing inputs supraspinal structures on CPGs, shortly after their formation. cord transected thoracic level [postnatal day 0 (P0)]. We examined postnatal week capacity CPGs produce...

GABA and glycine are excitatory in the immature spinal cord become inhibitory during development. The shift from depolarizing to hyperpolarizing postsynaptic potentials (IPSPs) occurs perinatal period rat, a time window which projections brain stem reach lumbar enlargement. In this study, we investigated effects of suppressing influences on motoneurons critical for negative reversal potential IPSPs ( E IPSP ). was transected at thoracic level day birth [postnatal 0 (P0)]. , P4–P7,...

Serotonin (5-HT) plays an important role both in the development and recovery of locomotion after spinalization vertebrates. We investigated contribution serotonergic system to maturation lumbar motoneurons networks neonatal rat. A 5-HT synthesis inhibitor, p-chlorophenylalanine (PCPA), was administered daily from first postnatal day (P0) onward. This protocol depleted serotonin spinal cord within 3-4 d, as demonstrated by immunohistochemistry. PCPA-treated rats exhibited postural changes...

The development of a number sensorimotor reflexes was studied in the Brazilian opossum Monodelphis domestica. At birth, an opossum's forelimbs execute rhythmic, alternate movements which resemble swimming, whereas hindlimbs are little more than embryonic buds that do not move independent trunk. It is possible, therefore, to witness entire hindlimb motility, advent coordination between and hindlimbs, ambulation. following sequence appearance maturation observed: rooting, innate reflex mammals...

The present study was carried out to characterize anatomically the vestibulospinal (VS) system of lampreys. Cobalt-lysine or Texas Red dextran amines were applied in vitro rostral spinal cord. Two distinct populations VS neurons labeled ventral nucleus area octavolateralis. group, comprising intermediate octavomotor (ION), contained between 100 and 150 neurons, having somata variable size morphology. Intracellular injections Lucifer Yellow single revealed ION with dendrites extending...

The opossum, Monodelphis domestica, is born very immature but crawls, unaided, with its forelimbs (FL) from the mother's birth canal to a nipple where it attaches pursue development. What sensory cues guide newborn and trigger attachment it? Previous experiments showed that low intensity electrical stimulation of trigeminal ganglion induces FL movement in vitro preparations innervation facial skin well developed newborn. does not contain Vater-Pacini or Meissner touch corpuscles at this age,...

The distribution of vestibular primary afferents as well their relationship with vestibulospinal and other brainstem neurons were studied in lampreys using anatomical tracers. Afferents from the anterior (aVIIIn) posterior (pVIIIn) branches nerve located mainly ventral nucleus octavolateral area. between was by applying one fluorescent tracer to whole or its another spinal cord. Some showed large, bulb-like enlargements (bulbs) about 20 these found intermediate octavomotor nucleus, whereas...

Marsupials are born very immature yet must be sufficiently autonomous to crawl on the mother's belly, find a teat and attach it pursue their development. Sensory inputs necessary guide newborn induce attachment. The vestibular system, which perceives gravity head movements, is one of senses proposed newborns towards teats but there conflicting observations about its functionality at birth (postnatal day (P) 0). To test if system opossum functional can influence locomotion, we used two...

ORIGINAL RESEARCH article Front. Neuroanat., 15 May 2013 https://doi.org/10.3389/fnana.2013.00012

We use opossums Monodelphis domestica to study the development of mammalian motor systems. The immature forelimbs newborn perform rhythmic and alternating movements that are likely under spinal control. hindlimbs start moving in second week. Chemical synapses scant enlargements neonatal presence electrochemical has not been evaluated this species or other marsupials. As a first step aiming at evaluating existence such cord, we have investigated exclusively neuronal gap junction protein...

External thermosensation is crucial to regulate animal behavior and homeostasis, but the development of mammalian thermosensory system not well known. We investigated whether temperature could play a role in control movements model born very immature, opossum (Monodelphis domestica). Like other marsupials, at birth performs alternate rhythmic with its forelimbs (FLs) reach teat where it attaches order continue development. It was shown that FL can be induced by mechanical stimulation snout...