Cross references: Red Nucleus Red Nucleus Evolution
Myoglobin Myoglobin Evolution Heme Globin
Cerebellum Muscle Innervation Motor Neuron Evolution
Motor Nerve Organization Medial Motor Column
Fast vs. Slow Twitch Muscles Shark Muscles
Searching Google for "red nucleus cerebellum" yielded 567,000 claimed references. These are all from the first page.
Nature of the cerebellar influences upon the red nucleus neurones - 1968 (Goog)
"Large cells in the red nucleus of cats were impaled with glass microelectrodes. Under light Nembutal anesthesia it was found that stimulation of the cerebellar cortex produced hyperpolarization in their membrane.
Unlike the inhibitory postsynaptic potentials, this hyperpolarization decreased when the membrane was depolarized by passage of currents through the microelectrode, and it increased during application of hyperpolarizing currents: Hence the hyperpolarization is presumed to be produced by removal of tonically impinging excitatory postsynaptic potentials, in the manner of “disfacilitation”. In accordance with the above view, spontaneously arising small EPSPs disappeared during the phase of the hyperpolarization.
The source of tonic impingement of excitatory impulses onto the red nucleus was found in the interpositus nucleus. The cells in this nucleus were discharging impulses at frequencies of 50–100/sec which were suppressed after the cerebellar stimulation, presumably via Purkinje cell axons, a depression in the excitability of the interpositus neurones being revealed at the same time. Following the depression, the excitability and impulse discharges of the interpositus neurones were enhanced, and correspondingly there was a late depolarization in the red nucleus neurones. During stimulation of the inferior olive and even of the spinal cord, disfacilitation and late facilitation occurred similarly through the interpositus nucleus, though with longer latencies."
1. Although I don't really understand this, "The source of tonic impingement of excitatory impulses onto the red nucleus was found in the interpositus nucleus." sounds like innervation of red muscle.
2. There were 35 references, but, judging from their titles, none of them seemed helpful.Effects of red nucleus inactivation on burst discharge in turtle cerebellum in vitro: evidence for positive feedback. - 1996 (Goog) http://www.ncbi.nlm.nih.gov/pubmed/8899595
Only abstract available online.
"In behaving animals the red nucleus produces sustained action potential discharge during movements of the limbs."
"The results showed that sustained discharge in the cerebellum was significantly attenuated by inactivation of the red nucleus even though sensory input that may trigger the bursts was intact. These data support the hypothesis that sustained discharge in the cerebellorubral circuit is generated by a distributed neuronal network that uses positive feedback."
"sustained discharge" sounds like nerves innervating red, rather than white, muscles.
The human red nucleus and lateral cerebellum in supporting roles for sensory information processing. - 2000 (Goog)
"The red and dentate nuclei were about 300% more active (a combination of activation areas and intensities) during passive (non-motor) tactile stimulation when discrimination was required than when it was not. Thus, the red nucleus was activated by purely sensory stimuli even in the absence of the opportunity to coordinate finger movements or to use the sensory cues to guide movement.
The red and dentate nuclei were about 70% more active during active tactile tasks when discrimination was required than when it was not (i.e., for simple finger movements alone). Thus, the red nucleus was most active when the fingers were being used for tactile sensory discrimination.
In both the passive and active tactile tasks, the observed activation had a contralateralized pattern, with stronger activation in the left red nucleus and right dentate nucleus. Significant covariation was observed between activity in the red nucleus and the contralateral dentate during the discrimination tasks and no significant correlation between the red nucleus and the contralateral dentate activity was detected during the two non-discrimination tasks.
The observed interregional covariance and contralateralized activation patterns suggest strong functional connectivity during tactile discrimination tasks. Overall, the pattern of findings suggests that the activity in the red nucleus, as in the lateral cerebellum, is more driven by the requirements for sensory processing than by motor coordination per se."
1. I'm very surprised. I had thought that the red nucleus was strictly, or at least predominantly motor.
2. The " stronger activation in the left red nucleus and right dentate nucleus" is just the sort of lateralization I was hoping to find. It suggests a possible bridge between cerebral laterality and the red-white muscle dichotomy.
3. As of 12/23/13 "Search this site" found 8 instances, including some duplication, of "contralateral" in this site:
4. There was a very interesting "Cited by".
"Distinct cerebellar contributions to intrinsic connectivity networks."
See: Cerebellum .
Cerebellar input to magnocellular neurons in the red nucleus of the mouse: synaptic analysis in horizontal brain slices incorporating cerebello-rubral pathways. - 2002 (Goog)
"In summary we propose that the special properties of the NMDA receptor components are considered important for the generation of RNm motor commands : their slow time course will contribute a steady driving force for sustained
discharge and their voltage dependency will facilitate abrupt transitions from a resting state of quiescence to an active state of intense motor command generation"
"slow time course will contribute a steady driving force for sustained
discharge" sounds like nerves innervating red muscle while "abrupt transitions from a resting state of quiescence to an active state of intense motor command generation" sounds like nerves innervating white muscle.