Decrease of ethanol intake following repeated injection of serotonin-1A agonist in rats: relationship with receptor responsiveness.
OBJECTIVE
To monitor pre and postsynaptic receptor responsiveness and consumption of ethanol following the repeated administration of a selective serotonin-1A receptor agonist, 8-hydroxy-2-di-n-propylaminotetralin (8-OH-DPAT), to ethanol treated rats.


METHODS
The experimental protocol was designed to administer ethanol orally to rats for three weeks and 8-OH-DPAT during the 3rd week.


METHODS
The experiments were performed in the department of Biochemistry, Karachi University. Samples collected after three weeks of treatment were analyzed within a week.


METHODS
The study was conducted on 24 males albino Wistar rats treated with ethanol for three weeks. 8-OH-DPAT at a dose of 1mg/kg or saline was injected to ethanol treated rats from day 1 to day 5 during the 3rd week to monitor the effects on ethanol consumption. Pre and postsynaptic responses to 8-OH-DPAT were monitored by injecting the drug on the 6th day to a group of 5-day saline and a group of 5-day 8-OH-DPAT injected animals. Control animals of the two groups were injected with saline.


RESULTS
Before the injection of 8-OH-DPAT, weekly intakes of ethanol were highly comparable in the two groups. Administration of 8-OH-DPAT, from day 1 to day 5, decreased ethanol intake. Pre and postsynaptic serotonin-1A receptor dependent responses monitored on the 6th day were higher in 5-day saline than 5-day 8-OH-DPAT injected animals.


CONCLUSIONS
A decrease in the effectiveness of negative feedback control over the synaptic availability of serotonin following 5-day administration of 8-OH-DPAT is involved in the decreases of ethanol consumption.
Hasnat
Ambreen
A
Department of Biochemistry, Neurochemistry and Biochemical Neurophamacology Research Unit, University of Karachi, Pakistan.
Haider
Saida
S
Perveen
Tahira
T
Kidwai
I M
IM
Haleem
Darakhshan J
DJ
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000008:administration & dosage* / Q000378:metabolism; D000428:Alcohol Drinking / Q000188:drug therapy / Q000378:metabolism*; D000818:Animals; D000431:Ethanol / Q000378:metabolism*; D025461:Feedback, Physiological / Q000502:physiology; D008297:Male; D023421:Models, Animal; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000378:metabolism; D017366:Serotonin Receptor Agonists / Q000008:administration & dosage* / Q000378:metabolism
D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; D000431:Ethanol; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin