Low doses (10 ng) of the dopamine agonist apomorphine induced hypolocomotion when injected into the nucleus accumbens of rats. This behavioral response was antagonized by local treatment with either the opioid peptide gamma-endorphin (gamma E) or the non-opioid peptide N alpha-acetyl-gamma-endorphin (Ac gamma E) in a dose of 100 pg. High doses of apomorphine (10 micrograms) r amphetamine (2 micrograms) injected into the nucleus accumbens resulted in hyperlocomotion. This response was blocked by pretreatment with gamma E but not with Ac gamma E. This effect of gamma E could be prevented by local treatment with naloxone. Neither peptides interfered with the apomorphine-induced stereotyped sniffing when the substances were injected into the nucleus caudatus. It is concluded that gamma E and Ac gamma E differentially interact with distinct dopaminergic systems in the nucleus accumbens of the rat brain via an opioid and a non-opioid mechanism, suggesting that the peptide fragments originating from pro-opiomelanocortin may be specifically implicated in the control of dopaminergic activity in this brain area.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0024-3205(84)90002-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Rescue-like behavior in a bystander mouse toward anesthetized conspecifics promotes arousal via a tongue-brain connection.
Sci Adv
January 2025
Department of Pain Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China.
Prosocial behaviors are advantageous to social species, but the neural mechanism(s) through which others receive benefit remain unknown. Here, we found that bystander mice display rescue-like behavior (tongue dragging) toward anesthetized cagemates and found that this tongue dragging promotes arousal from anesthesia through a direct tongue-brain circuit. We found that a direct circuit from the tongue → glutamatergic neurons in the mesencephalic trigeminal nucleus (MTN) → noradrenergic neurons in the locus coeruleus (LC) drives rapid arousal in the anesthetized mice that receive the rescue-like behavior from bystanders.
View Article and Find Full Text PDFAltered asymmetry of amygdala volume mediates food addiction and weight gain.
J Behav Addict
January 2025
1Department of Metabolic & Bariatric Surgery, Shanghai Jiao Tong University School of Medicine Affiliated Sixth People's Hospital, Shanghai, 200233, China.
Background: Food addiction and an impulsive personality can increase overeating, which can lead to weight gain. The amygdala and nucleus accumbens (NAcc) are critical for regulating obesogenic behaviour. However, whether the amygdala or the NAcc acts as the neural basis for the regulation of food addiction, impulsive personality, and body weight remains unclear.
View Article and Find Full Text PDFAim: The Transorbital and supraorbital minimally invasive approaches have been defined to reach intraorbital structures, adjacent sinuses, skull base, and other intracranial targets in this region. These approaches reduce the possible cosmetic and brain retraction-related morbidities caused by traditional transcranial approaches. Although these pathways are being studied endoscopically, a stereotactic approach has not been defined.
View Article and Find Full Text PDFMaternal exposure to dim light at night induces behavioral alterations in the adolescent and adult offspring Wistar rat.
Front Physiol
January 2025
Departamento de Anatomía, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Introduction: Access to electric light has exposed living organisms to varying intensities of light throughout the 24 h day. Dim light at night (DLAN) is an inappropriate signal for the biological clock, which is responsible for the circadian organization of physiology. During the gestational period, physiological adaptations occur to ensure a successful pregnancy and optimal fetal development.
View Article and Find Full Text PDFPersistently increased post-stress activity of paraventricular thalamic neurons is essential for the emergence of stress-induced alterations in behaviour.
PLoS Biol
January 2025
Lendület Laboratory of Thalamus Research, HUN-REN Institute of Experimental Medicine, Budapest, Hungary.
A single exposure to a stressful event can result in enduring changes in behaviour. Long-term modifications in neuronal networks induced by stress are well explored but the initial steps leading to these alterations remain incompletely understood. In this study, we found that acute stress exposure triggers an immediate increase in the firing activity of calretinin-positive neurons in the paraventricular thalamic nucleus (PVT/CR+) that persists for several days in mice.
View Article and Find Full Text PDFWant 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!