Axonal transport of [3H]proteins in a noradrenergic system of the rat brain.
Proteins synthesized from [3H]leucine injected into the rat nucleus locus coeruleus (LC) were transported through the hypothalamus in 5 successive waves at rates of 72-192, 24-48, 13-20, 3-4 and 1.4-2.9 mm/day (waves I through V, respectively). Waves I through IV began axoplasmic transport in the LC within the first few hours after [3H]protein synthesis began in the LC. Wave V was delayed in onset for 1.7-3.7 days and was also probably transported through the contralateral hypothalamus. Wave IV was not transported within the LC-hypothalamic axons ascending through the dorsal noradrenergic bundle since its transport was not blocked by 6-OHDA lesions in this bundle, as was transport of the other 4 waves. Unilateral dorsal bundle lesions caused a well defined caudal backup of dopamine-beta-hydroxylase immunofluorescence and a fall in dopamine-beta-hydroxylase activity in the ipsilateral frontal cortex and hypothalamus of 55% and 9%, respectively. Bilateral lesions caused only a significantly further reduction in hypothalamic levels indicating crossed innervation of the hypothalamus by the LC of 27%. Waves I and II have been classified as rapid transport and contained 33% of the transported [3H]protein. Wave V was slowly transported and contained 51% of the transported [3H]protein, while wave III was intermediate in rate and contained 16% of transported [3H]proteins.
D000320:Adrenergic Fibers / Q000378:metabolism*; D000818:Animals; D001370:Axonal Transport; D005625:Frontal Lobe / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism; D008125:Locus Coeruleus / Q000378:metabolism*; D008297:Male; D008474:Medial Forebrain Bundle / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D014316:Tritium
D009419:Nerve Tissue Proteins; D014316:Tritium; D007930:Leucine; D009638:Norepinephrine