Hibernation-Induction Trigger. I. Opioid-like Effects of Prairie Dog Plasma Albumin on Induced Contractility of Guinea Pig Ileum

• Published in: Pharmacology, biochemistry and behavior biochemistry and behavior, 1997-11, Vol.58 (3), p.621-625
• Main Authors: Bruce, D.S, Bailey, E.C, Crane, S.K, Oeltgen, P.R, Horton, N.D, Harlow, H.J
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Dose-Response Relationship, Drug; Fundamental and applied biological sciences. Psychology; Guinea pig ileum; Guinea Pigs; Hibernation; Hibernation - physiology; HIT; Ileum - drug effects; In Vitro Techniques; Male; Muscle Contraction - drug effects; Muscle, Smooth - drug effects; Myenteric Plexus - drug effects; Myenteric Plexus - physiology; Opioid; Prairie dog plasma; Receptors, Opioid - drug effects; Sciuridae - physiology; Serum Albumin - pharmacology; Species Specificity; Thermoregulation. Hibernation. Estivation. Ecophysiology and environmental effects; Vertebrates: anatomy and physiology, studies on body, several organs or systems
• ISSN: 0091-3057; 1873-5177
• DOI: 10.1016/S0091-3057(97)00063-4

BRUCE D. S., E. C. BAILEY, S. K. CRANE, P. R. OELTGEN, N. D. HORTON AND H. J. HARLOW. Hiber-nation-induction trigger. I. Opioid-like effects of prairie dog plasma albumin on induced contractility of guinea pig ileum. PHARMACOL BIOCHEM BEHAV 58(3) 621–625, 1997.—Studies have shown that plasma albumin fractions (PAFs) from hibernating mammals can inhibit induced contractility of the guinea pig ileum similarly to morphine. This study examined PAFs from two species of prairie dogs, one that undergoes natural seasonal hibernation (white-tailed, WT) and one that does not but can be induced to hibernate (black-tailed, BT). Dose–response curves of lyophilized PAF yielded IC 50 values (mg) of 20.23 for summer WT, 15.53 for hibernating WT, 15.45 for summer BT, and 13.16 for winter-active BT. Winter samples from both species have IC50s lower than samples from summer animals, indicating greater potency of winter PAFs in suppressing guinea pig ileum contractility and therefore the presence of more opioid ligands in winter prairie dog plasma. Studies to elucidate receptor selectivity of PAF continue.