Biomaterial Database

Effects of cocaine on adrenal sympathetic nerve discharge in anesthetized rats. 1998

T P Abrahams, and K J Varner

Department of Pharmacology and Experimental Therapeutics, Louisiana State University Medical Center, New Orleans 70112, USA.

Cocaine increases the circulating levels of plasma catecholamines, presumably via the activation of the sympathoadrenal axis. However, a number of reports have shown that the predominant response to cocaine is a generalized decrease in sympathetic nerve activity. One possible explanation for the increase in plasma catecholamines may be that the adrenal sympathetic nerve is less sensitive to the sympathoinhibitory actions of cocaine than are other nerves. This study compared the effects of cocaine on adrenal and renal sympathetic nerve discharge (SND) recorded simultaneously in pentobarbital-anesthetized rats. Cocaine produced dose-related decreases in both renal and adrenal SND; however, the decreases in adrenal SND were significantly smaller than in renal SND. Cocaine also elicited pressor responses in these rats. The decreases in adrenal SND were similar in baroreceptor intact and sinoaortically denervated rats, indicating that pressor-mediated baroreceptor reflex activation was not responsible for the decrease in adrenal SND. In a separate group of rats, i.v. administration of desipramine decreased both adrenal and renal SND. As with cocaine, the decreases in adrenal SND after desipramine were smaller, suggesting that the differences in the neural responses did not reflect a differential local anesthetic effect of cocaine on the two nerves. In conclusion, these studies showed that cocaine decreases adrenal SND in pentobarbital-anesthetized rats. However, the adrenal sympathetic nerve is less sensitive than the renal nerve to the sympathoinhibitory actions of cocaine. Whether the adrenal SND remaining after cocaine contributes to the increase in plasma catecholamines produced by this drug remains to be determined.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009294	Narcotics	Agents that induce NARCOSIS. Narcotics include agents that cause somnolence or induced sleep (STUPOR); natural or synthetic derivatives of OPIUM or MORPHINE or any substance that has such effects. They are potent inducers of ANALGESIA and OPIOID-RELATED DISORDERS.	Analgesics, Narcotic,Narcotic Analgesics,Narcotic,Narcotic Effect,Narcotic Effects,Effect, Narcotic,Effects, Narcotic
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D003042	Cocaine	An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake.	Cocaine HCl,Cocaine Hydrochloride,HCl, Cocaine,Hydrochloride, Cocaine
D003891	Desipramine	A tricyclic dibenzazepine compound that potentiates neurotransmission. Desipramine selectively blocks reuptake of norepinephrine from the neural synapse, and also appears to impair serotonin transport. This compound also possesses minor anticholinergic activity, through its affinity to muscarinic receptors.	Desmethylimipramine,Apo-Desipramine,Demethylimipramine,Desipramine Hydrochloride,Norpramin,Novo-Desipramine,Nu-Desipramine,PMS-Desipramine,Pertofran,Pertofrane,Pertrofran,Petylyl,Ratio-Desipramine,Apo Desipramine,Hydrochloride, Desipramine,Novo Desipramine,Nu Desipramine,PMS Desipramine,Ratio Desipramine
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D000311	Adrenal Glands	A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.	Adrenal Gland,Gland, Adrenal,Glands, Adrenal
D000758	Anesthesia	A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia