The effects of morphine (10mg/kg) on intracranial self-stimulation were studied in three separate test situations, each requiring rats to perform different types of responses. Self-stimulation was depressed in a test of rate of bar-pressing, to a lesser extent in a test of rate of wall-pressing in which a wider range of movements were reinforced, but not in a shuttle-box, with brain stimulation continuously available on one side of box. This resonse dependency suggests that the depressive effect of morphine on bar-pressing for lateral hypothalamic stimulation reflects a performance deficit rather than an effect on the reinforcing value of the stimulation.

Download full-text PDF

Source
http://dx.doi.org/10.1007/BF00426791DOI Listing

Publication Analysis

Top Keywords

effects morphine
8
lateral hypothalamic
8
test rate
8
response-dependent effects
4
morphine reinforcing
4
reinforcing lateral
4
hypothalamic self-stimulation
4
self-stimulation effects
4
morphine 10mg/kg
4
10mg/kg intracranial
4

Similar Publications

Decreased opioid receptor availability and impaired neurometabolic coupling as signatures of morphine tolerance in male rats: A positron emission tomography study.

Biomed Pharmacother

January 2025

Laboratoire d'Imagerie Biomédicale Multimodale (BioMaps), CEA, CNRS, Inserm, Service Hospitalier Frédéric Joliot, Université Paris-Saclay, Orsay, France. Electronic address:

Translational neuroimaging techniques are needed to address the impact of opioid tolerance on brain function and quantitatively monitor the impaired neuropharmacological response to opioids at the CNS level. A multiparametric PET study was conducted in rats. Rats received morphine daily to induce tolerance (15 mg/kg/day for 5 days), followed by 2-day withdrawal.

View Article and Find Full Text PDF

Importance: States have implemented multiple policies likely to influence opioid prescribing; few national general population studies examine those policies' effects on per-capita opioid morphine milligram equivalents (MME) dispensed.

Objective: To examine state policies' effects on opioids per-capita MMEs dispensed at retail pharmacies.

Design: A longitudinal study of associations between MME per capita and implementation of policy interventions at different times across states.

View Article and Find Full Text PDF

Opioid dependence is defined by an aversive withdrawal syndrome upon drug cessation that can motivate continued drug-taking, development of opioid use disorder, and precipitate relapse. An understudied but common opioid withdrawal symptom is disrupted sleep, reported as both insomnia and daytime sleepiness. Despite the prevalence and severity of sleep disturbances during opioid withdrawal, there is a gap in our understanding of their interactions.

View Article and Find Full Text PDF

Introduction: Since late 2019, SARS-CoV-2 has infected over 767 million people worldwide with over one million deaths in the United States alone. One risk factor identified for possible worse outcomes from the virus is medication-induced immune suppression. Some opioids have been associated with immunomodulatory effects.

View Article and Find Full Text PDF

Background: Nissen fundoplication is one of the most common surgical procedures for gastroesophageal reflux. Current and previous research comparing laparoscopic Nissen fundoplication (LNF) versus open Nissen fundoplication (ONF) in children suggest ambiguous conclusions. The purpose of this retrospective study was to compare the outcome for children operated with LNF or ONF at our institution and to evaluate the economic aspects.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!