Inverse relation of substance P-like immunoreactivity in dorsal raphe nucleus to serotonin levels in pons-medulla following administration of cocaine and 5-hydroxytryptophan

Autor: Sikta Pradhan, Glen R. Hanson, Walter Lovenberg
Rok vydání: 1981
Předmět:
Zdroj: Biochemical Pharmacology. 30:1071-1076
ISSN: 0006-2952
DOI: 10.1016/0006-2952(81)90444-5
Popis: Changes in levels of substance P-like immunoreactivity (SPLI) were observed in the rat dorsal raphe nucleus after cocaine treatment and were compared with concurrent cocaine-induced changes in 5-hydroxytryptamine (5-HT) content in the pons-medulla (PM). Acute administration of cocaine (15–30 mg/kg) consistently resulted in increases of SPLI, specifically in the area of the dorsal raphe nucleus, which were accompanied by significant decreases of PM 5-HT levels. Treatment of rats with 5-hydroxytryptophan (5-HTP), the 5-HT precursor, along with RO4-4602, the decarboxylase inhibitor, caused increments in PM 5-HT content with concurrent decreases in dorsal raphe nucleus SPLI. When cocaine and 5-HTP were administered simultaneously the changes in serotonin and SPLI were attenuated, suggesting that each substance antagonized the effect of the other. These data suggest a specific interaction between substance P and 5-HT in the dorsal raphe nucleus area.
Databáze: OpenAIRE