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PubMed · 133361

Effect of dihydroxyphenylalanine, imipramine and coffeine on the light induced decrease in nocturnal serotonin N-acetyltransferase in the rat pineal gland.

J Vanĕcek·H Illnerová
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Abstract

The s.c. administration of 150mg L-dihydroxphyenylalaine/kg b.w. 15 min before the decapitation prevents the light induced decrease in nocturnal serotonin N-acetyltransferase activity in the rat pineal gland. The s.c. administration of 50mg imipramine/kg b.w., resp. 100mg/kg b.w., 15 min before the decapitation, slows down, or prevents the light induced fall in the activity. The maintenance of a sufficient level of active norepinephrine on beta-receptors, either by displacement of norepinephrine in the nerve endings by dopamine, or by the inhibition of norepinephrine reuptake by imipramine, thus slows down or prevents the decrease in serotonin N-acetyltransferase activity after exposure to light during the night. The i.p. administration of a phosphodiesterase inhibitor coffeine citrate in a dose 200mg/kg 90 min after switching off the light for the night stimulated serotonin N-acetyltransferase activity 270 min after the light and been switched off, but did not influence the abrupt decrease induced in nocturnal activity by exposure to light.

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AcetyltransferasesAnimalsCaffeineDarknessDihydroxyphenylalanineImipramineLightMalePineal GlandRatsSerotoninJournal Article

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J Vanĕcek, H Illnerová. 1976. Effect of dihydroxyphenylalanine, imipramine and coffeine on the light induced decrease in nocturnal serotonin N-acetyltransferase in the rat pineal gland.. https://pubmed.ncbi.nlm.nih.gov/133361/

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