Effects of estradiol valerate on voluntary alcohol consumption, beta-endorphin content and neuronal population in hypothalamic arcuate nucleus.
The main goal of the present experiment was to study the voluntary consumption of alcohol before and after a single injection of estradiol valerate (EV); another goal was to assess beta-endorphin (beta-EP) neurons and beta-EP peptide in hypothalamic arcuate nucleus 10 weeks after the injection of EV. Wistar female rats were injected either with a single 2.0 mg/rat injection of EV or with 0.2 ml of corn oil/rat (vehicle group). Two weeks before the injection and 10 weeks after it, every other day both groups were exposed to a free-choice alcohol drinking procedure. In weeks 4 and 5, the post-injection-consumption of alcohol was higher in the EV group than the vehicle group. In the EV group, food intake decreased and coincided with body weight lost in week 1 of post-EV injection. EV treated females showed significantly lower number of beta-EP neurons than control group (reduction of 51.22%); however, beta-EP content was similar in both groups, and they did not differ in the number of TSH and LHRH neurons. The present results suggest a positive relationship between high alcohol consumption and possible initial deficiency of beta-endorphin content. The transient increase in alcohol consumption suggests a possible compensatory secretory effect of the surviving beta-endorphinergic neurons, particularly when they are chronically stimulated with alcohol.
Juárez
Jorge
J
Laboratorio de Farmacología y Conducta, Instituto de Neurociencias, CUCBA, Universidad de Guadalajara, Guadalajara, Jalisco, México. jjuarez@cencar.udg.mx
Camargo
Gabriela
G
Gómez-Pinedo
Ulises
U
D000428:Alcohol Drinking; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000166:cytology / Q000378:metabolism*; D001835:Body Weight; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D007150:Immunohistochemistry; D009474:Neurons / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D001615:beta-Endorphin / Q000378:metabolism*
D004958:Estradiol; D001615:beta-Endorphin