Related Experiment Video
Updated: Jul 17, 2026
Using Optogenetics to Reverse Neuroplasticity and Inhibit Cocaine Seeking in Rats
Published on: October 5, 2021
Involvement of nitric oxide in cocaine-induced erections and ejaculations after paradoxical sleep deprivation
Monica L Andersen1, Juliana C Perry, Isabela B Antunes
1Department of Psychobiology - Universidade Federal de São Paulo, Escola Paulista de Medicina (UNIFESP/EPM), R. Napoleão de Barros, 925, V. Clementino 04024-002, São Paulo, SP, Brazil. mandersen@psicobio.epm.br
Objectives:
As nitric oxide (NO) is involved in penile erectile (PE) function and also influences the sleep-wake cycle, we speculated that NO could play a role in PE and ejaculation of paradonical sleep deprivation (PSD) rats.
Methods:
Animals were pretreated with N(G)-nitro-L-arginine methyl ester (L-NAME, ip) and L-arginine (ip and icv) prior to saline or cocaine injection.
Results:
Cocaine-induced PE in 90% of PSD rats, 60% of which ejaculated. L-NAME reduced the frequency of erection, but had no effect in the proportion of PSD-cocaine-injected rats displaying this response. L-NAME had no effect in saline groups. L-Arginine in PSD-saline rats reduced the proportion of animals displaying PE at the highest dose and reduced the frequency of PE at all doses in both saline and cocaine groups. The icv administration of L-arginine reduced PE only in PSD-cocaine rats. Results indicate that common to both drugs, whether it was NO synthase (NOS) inhibitor or NO precursor, was their capacity to strongly reduce PE frequency in cocaine-treated rats. Moreover, L-arginine (ip) played a relevant inhibitory role in the erection displayed by PSD rats.
Conclusions:
Our findings suggest that the stimulating effects of PSD associated or not with cocaine on erection can be modified by alterations in the NO system.
Related Concept Videos
01:28Nitric Oxide Signaling Pathway
01:17Male Sexual Response: Erection & Ejaculation
The blood filling the erectile tissues compresses the veins, which helps to prevent blood from leaving...
01:25Adrenergic Agonists: Indirect-Acting Agents
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
01:24Substance Use Disorders Affecting Sleep
Understanding the concepts of physical dependence,...
01:23Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...
01:24CNS Stimulants: Cocaine, Amphetamines and Cannabinoids