title: Effects of environmental lighting, superior cervical ganglionectomy and adrenergic drugs on microtubule protein levels of the rat hypothalamus.
abstract: Bilateral superior cervical ganglionectomy or exposure of rats to light for 10 days resulted in comparable increases in microtubule protein content in the hypothalamus. Administration of norepinephrine, L-dopa or isoproterenol decreased hypothalamic tubulin levels to a greater extent in ganglionectomized rats. A prior injection of phentolamine prevented norepinphrine's effects in intact rats and decreased but did not abolish the effect of the catecholamine in ganglionectomized animals. Phentolamine impaired L-dopa activity in intact and denervated rats as did propranolol; beta-adrenergic blockage impaired the effect of norepinephrine in denervated rats and abolished that of isoproterenol. Phentolamine plus propranolol prevented norepinephrine's effects whereas it only impaired L-dopa activity on hypothalamic tubulin content. The prior administration of actinomycin D blocked the effects of norepinephrine, L-dopa or isoproterenol. Pinealectomy abolished the isoproterenol-induced decrease in microtubule protein content and impaired that following L-dopa. These data suggest that tubulin levels of the rat hypothalamus are controlled by adrenergic transmitter via alpha- and beta-receptors, the latter involving the pineal gland.
mesh_terms: D000818:Animals; D001337:Autonomic Agents / Q000494:pharmacology*; D003609:Dactinomycin / Q000494:pharmacology; D005725:Ganglia, Autonomic / Q000378:metabolism / Q000601:surgery; D007031:Hypothalamus / Q000378:metabolism*; D007545:Isoproterenol / Q000494:pharmacology; D007980:Levodopa / Q000494:pharmacology; D008027:Light; D008297:Male; D008870:Microtubules / Q000032:analysis* / Q000187:drug effects / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000032:analysis*; D009434:Neural Pathways; D009638:Norepinephrine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats
chemical_list: D001337:Autonomic Agents; D009419:Nerve Tissue Proteins; D003609:Dactinomycin; D007980:Levodopa; D011433:Propranolol; D007545:Isoproterenol; D009638:Norepinephrine; D010646:Phentolamine