The authors' objective was to obtain information on biosynthesis of prostaglandins (PGs) in the rat brain following administration of a hyperthermic dose of the endogenous opioid met-enkephalin. Brain homogenates from met-enkephalin-treated rats exhibited an increase in PG biosynthesis in comparison of saline treated animals (38.42 ± 3.80 to 97.11 ± 5.19 ng/g wet wt, p < 0.05). This increase was prevented by naloxone 3 mg/kg/s.c. Chronic met-enkephalin administration resulted in a normalization of PGs in rat brain. A relationship could be admitted between generation of prostaglandins in the brain after acute administration of met-enkephalin and the hyperthermic effect elicited by the opioid in the rat. Normalization of PGs biosynthesis following chronic administration of met-enkephalin could also account for the tolerance to its thermic effect.
Met-enkephalin induced changes in rat brain prostaglandins
SCOTO, Giovanna Maria;
1978-01-01
Abstract
The authors' objective was to obtain information on biosynthesis of prostaglandins (PGs) in the rat brain following administration of a hyperthermic dose of the endogenous opioid met-enkephalin. Brain homogenates from met-enkephalin-treated rats exhibited an increase in PG biosynthesis in comparison of saline treated animals (38.42 ± 3.80 to 97.11 ± 5.19 ng/g wet wt, p < 0.05). This increase was prevented by naloxone 3 mg/kg/s.c. Chronic met-enkephalin administration resulted in a normalization of PGs in rat brain. A relationship could be admitted between generation of prostaglandins in the brain after acute administration of met-enkephalin and the hyperthermic effect elicited by the opioid in the rat. Normalization of PGs biosynthesis following chronic administration of met-enkephalin could also account for the tolerance to its thermic effect.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
