title: Comparison of the effects of Althesin, chloralose-urethane, urethane, and pentobarbital on mammalian physiologic responses.
abstract: Physiological responses to anesthetic doses of four chemically dissimilar agents, namely, Althesin, urethane, chloralose-urethane, and pentobarbital sodium were compared in rats. The tail-flick test revealed Althesin had greater antinociceptive potency than urethane, chloralose-urethane, and pentobarbital, but its duration of action was shorter than that of chloralose-urethane. Althesin produced minimal or no suppression of core body temperature and mean arterial pressure, and only moderate reduction of mean pulse pressure. The heart rate and respiratory rate of Althesin-treated rats were slower than those of chloralose-urethane and urethane-treated counterparts, respectively, but were not significantly decreased from normal controls. It is concluded that Althesin is a suitable anesthetic for short-term surgery and for studies of body temperature, heart rate, and mean arterial pressure. Because release of gonadotropin-releasing hormone into hypophysial portal blood can be observed under Althesin but is suppressed or blocked by chloralose-urethane, urethane, and pentobarbital, Althesin is the anesthetic of choice in studies concerned with the neural control of ovulatory hormone release.
mesh_terms: D000530:Alfaxalone Alfadolone Mixture / Q000494:pharmacology; D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D002698:Chloralose / Q000494:pharmacology; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D009619:Nociceptors / Q000187:drug effects; D010424:Pentobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000187:drug effects; D012119:Respiration / Q000187:drug effects; D013997:Time Factors; D014520:Urethane / Q000494:pharmacology
chemical_list: D000777:Anesthetics; D002698:Chloralose; D014520:Urethane; D000530:Alfaxalone Alfadolone Mixture; D010424:Pentobarbital