[Effects of microinjection of tutin into nucleus tractus solitarius region on the morphology of neural tissue of this area in rabbit].
Four hours after unilateral microinjection of tutin (10 micrograms) into the NTS region, the nervous tissue surrounding the center of microinjection showed the following morphologic changes: 1. Under the light microscopic examination (n = 5), the neuronal body showed chromatolysis and the nuclear basophilia enhanced in about 17% of the neurons, the lacunae of neuropil distended and gave a "spongy" appearance. The neurons with lesion mingled with the normal ones in the absence of distinct demarcation. 2. Under the electron microscopic examination (n = 3), the cisterns of rough endoplasmic reticulum distended, and the nuclear electron density increased on account of the increased nuclear chromatin in the affected cells. The organelles of dendrites decreased or disappeared; the neuroglia looked edematous. There were only a few axons which looked edematous in the neuropil. Microinjection of the same volume (1 microliter) of NS into the other side of NTS region in the same rabbit didn't show any sign of damage as those described above. Thus, our preliminary results suggest that tutin might damage the soma and dendrites of some neurons, and therefore, it might be a neuroexcitotoxin.
Department of Physiology, Chengdu Institute of Biology, Academic Sinica.
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Y
Jiang
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M
Xu
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Wu
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Chen
D000818:Animals; D000697:Central Nervous System Stimulants; D008526:Medulla Oblongata / Q000187:drug effects* / Q000648:ultrastructure; D008845:Microinjections; D009474:Neurons / Q000187:drug effects; D010852:Picrotoxin / Q000031:analogs & derivatives; D011817:Rabbits; D012717:Sesquiterpenes / Q000494:pharmacology*
D000697:Central Nervous System Stimulants; D010852:Picrotoxin; D012717:Sesquiterpenes; C009614:tutin