GHB-C rats: the control line of GHB-sensitive (GHB-S) and GHB-resistant (GHB-R) rats.
Gamma-hydroxybutyric acid (GHB)-sensitive (GHB-S) and GHB-resistant (GHB-R) rats have been selectively bred for their opposite sensitivity to the sedative/hypnotic effect of GHB. This opposite sensitivity has been found to generalize to the GABA(B) receptor agonist, baclofen. A control line [named GHB-control (GHB-C)] has been derived from the foundation stock of GHB-S and GHB-R rats. GHB-C rats have been bred without any evaluation of their sensitivity to GHB. The experiments described here were designed to evaluate the sensitivity of GHB-C rats, from the 13th generation, to the sedative/hypnotic effect of GHB (1 g/kg, i.p.) and baclofen (20 mg/kg, i.p.). All measures (onset, sleep time and r = sleep time/onset) of sensitivity to GHB- and baclofen-induced sedation/hypnosis in GHB-C rats were significantly different from and intermediate to those recorded in GHB-S and GHB-R rats. Furthermore, these values were similar to those recorded in the foundation stock. These results suggest that GHB-C rats may constitute a valid control line for GHB-S and GHB-R rats, representing the "general population" from which GHB-S and GHB-R rats were derived. Furthermore, the relative equidistance of sensitivity to GHB- and baclofen-induced sedation/hypnosis of GHB-C rats from those of GHB-S and GHB-R rats suggests that genetic factors contributes to the development of both sensitivity in GHB-S rats and resistance in GHB-R rats.
Lobina
Carla
C
Brodie Department of Neuroscience, University of Cagliari, Viale Diaz 182, I-09126 Cagliari, Italy.
Colombo
Giancarlo
G
Orrù
Alessandro
A
Maccioni
Paola
P
Gessa
Gian Luigi
GL
Carai
Mauro A M
MA
D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D004351:Drug Resistance; D005260:Female; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D008297:Male; D009125:Muscle Relaxants, Central / Q000494:pharmacology; D004856:Postural Balance / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains / Q000502:physiology*; D012727:Sex Characteristics; D012890:Sleep / Q000187:drug effects; D012978:Sodium Oxybate / Q000494:pharmacology*
D006993:Hypnotics and Sedatives; D009125:Muscle Relaxants, Central; D012978:Sodium Oxybate; D001418:Baclofen