Adrenocorticotropin release is not involved in the nicotine-induced reversal of hemorrhagic shock in anesthetized rats.
In a model of volume-controlled hemorrhagic shock causing the death of all control animals within 30 min, the intravenous injection of nicotine produced a rapid, sustained and dose-dependent restoration of cardiovascular and respiratory functions, with 60 and 100% survival 2 h after the administration of 3 and 12 micrograms/kg, respectively. An effect similar to that of the highest dose of nicotine were obtained with the intravenous bolus injection of ACTH(1-24) at the dose of 160 micrograms/kg. However, the ACTH plasma levels of hemorrhage-shocked rats treated with nicotine was not different from that of hemorrhage-shocked rats treated with saline, thus excluding the possibility that nicotine-induced shock reversal may be due to the massive release of ACTH. Since in rats pretreated with cycloheximide at a dose (20 mg/kg intraperitoneally) causing an 82% inhibition of protein synthesis, and then bled to hemorrhagic shock, the effect of nicotine was greatly reduced (only the dose of 50 micrograms/kg producing 100% survival 2 h after treatment), protein synthesis, however, seems to be important for the effect of nicotine in hemorrhagic shock, at least at the lowest doses.
Bazzani
C
C
Department of Biomedical Sciences, University of Modena, Italy.
Bertolini
A
A
Casalgrandi
L
L
Bertolini
E
E
Balugani
A
A
Fiore
L
L
Guarini
S
S
D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003513:Cycloheximide / Q000494:pharmacology; D005260:Female; D008297:Male; D009538:Nicotine / Q000627:therapeutic use*; D014176:Protein Biosynthesis; D051381:Rats; D017208:Rats, Wistar; D012771:Shock, Hemorrhagic / Q000188:drug therapy*
D009538:Nicotine; D000324:Adrenocorticotropic Hormone; D003513:Cycloheximide