2024-03-29T12:49:58Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/365362019-05-31T12:13:27Zcom_10261_54com_10261_1col_10261_307
00925njm 22002777a 4500
dc
Borcel, E.
author
Pérez-Álvarez, L.
author
Ceballos, María L. de
author
Ramírez, Belén G.
author
Marco, Eva María
author
Fernández, Beatriz
author
Rubio, Marina
author
Guaza, Carmen
author
Viveros, M. Paz
author
2004
We have studied behavioural, biochemical and endocrine responses to the cannabinoid agonist WIN 55,212-2 (WIN) in neonatal rats, as well as the effects of weaning on such responses. We used preweanling rats (20 days of age), 25-day-old weaned rats (weaning at Day 22) and 25-day-old nonweaned rats of both sexes. The behavioural effects of WIN were assessed in the nociceptive tail immersion test and in the open field. We also analysed the effect of weaning on corticosterone responses to WIN (radioimmunoassay) as well as on WIN-stimulated [35S] GTPgammaS binding in periaqueductal grey (PAG) and striatum. The cannabinoid agonist induced a modest increase in pain thresholds, whereas the effect of the drug on open-field activity, particularly on vertical activity, was much more marked. The weaning process appeared to reduce the baseline nociceptive latencies of the female rats. No significant effect of weaning on the behavioural responses to WIN was found. However, the group of weaned females (but not males) showed a significantly reduced WIN-stimulated [35S] GTPgammaS binding in the striatum. The cannabinoid agonist significantly increased the corticosterone levels of 25-day-old rats with the effect being more marked in weaned than in nonweaned animals. The results suggest that the weaning process might produce some sexually dimorphic developmental changes in CB1 receptor function
Pharmacology, Biochemistry and Behavior 78: 593-602 (2004)
0091-3057
http://hdl.handle.net/10261/36536
10.1016/j.pbb.2004.02.020
Rat
Weaning
WIN 55,212-2
Nociception
Corticosterone
Cannabinoid agonist-stimulated [35S] GTPγS binding
Functional responses to the cannabinoid agonist WIN 55,212-2 in neonatal rats of both genders: influence of weaning