Cocaine-elicited mydriasis in the rat: pharmacological comparison to clonidine, D-amphetamine and desipramine
by
Pitts DK, Marwah J.
Neuroscience Laboratory,
Wayne State University,
Detroit, Michigan.
J Pharmacol Exp Ther. 1988 Dec;247(3):815-23
ABSTRACTAgents known to influence adrenergic function were examined for their mydriatic effects in urethane-anesthetized rats. Both the direct acting adrenergic agonist, clonidine, and the "indirect" acting agonists, cocaine, desipramine and amphetamine elicited mydriatic responses. The polar alpha-2 adrenoceptor agonist, 4-hydroxyclonidine, did not elicit a mydriatic response when administered systemically; however, it did produce a pronounced mydriatic response when administered i.c.v. Inasmuch as the selective lipophilic alpha-2 adrenoceptor antagonist, yohimbine, but not the polar alpha adrenoceptor antagonist, phentolamine, reversed the mydriatic effects of clonidine and cocaine, these data suggest that centrally located alpha-2 adrenoceptors elicit the above mydriatic response. The direct acting alpha-2 adrenoceptor agonists, clonidine (i.v.) and 4-hydroxyclonidine (i.c.v.), were the most efficacious of the agents studied in eliciting the mydriatic response. The indirect acting agents, amphetamine, desipramine and cocaine, were less efficacious. The rank order potency (ED-50) of these drugs was as follows: clonidine greater than desipramine greater than cocaine = amphetamine. The mydriatic effects of cocaine were attenuated by yohimbine and reserpine pretreatments. In addition, the local anesthetic, procaine, and the polar cocaine analog, cocaine methiodide, were significantly less efficacious than cocaine. These results suggest that cocaine elicits mydriasis by indirectly acting at central and postsynaptically located alpha-2 adrenoceptors.Users
History
Twin study
Mu and kappa
Quails on coke
Crack and crime
Drug education?
Prenatal cocaine
Dopaminergic flies?
Dopaminergic agents
Coca leaves/cocaine
Cocaine immunization
The coke-craving brain
Cocaine and methylphenidate
Cocaine, dopamine, noradrenaline and serotonin
Sigma antagonists in the treatment of cocaine addiction
Do sigma1 agonists like igmesine make cocaine more rewarding?
01 02 03 04 05 06 07 08 09 10 11 12
13 14 15 16 17 18 19 20 21 22 23 24
Refs
HOME
HedWeb
Future Opioids
BLTC Research
Amphetamines.com
Wirehead Hedonism
Paradise-Engineering
The Hedonistic Imperative
MDMA: Utopian Pharmacology
When Is It Best to Take Crack Cocaine?
The Good Drug Guide
The Responsible Parent's Guide To
Healthy Mood Boosters For All The Family
