Strain differences in the magnitude of swimming-induced analgesia in mice correlate with brain opiate receptor concentration.
Swimming-induced analgesia was studied in 4 strains of mice differing in central opiate receptor density: C57BL/6By (C57), BALB/cBy (BALB/c), CXBK and CXBH. The degree of 'swim analgesia' significantly differed among strains in the order CXBH greater than BALB/c = C57 greater than CXBK. This order positively correlates with known differences in opiate receptor density in these strains. Naloxone reversed the analgesic effect of swimming in CXBH, C57 and BALB/c, but was ineffective in opiate receptor-deficient CXBK mice. These results suggest that genetic differences in central opiate receptor density influence the analgesic response to stressful stimuli.
Marek
P
P
Department of Behavioral Physiology, Polish Academy of Sciences, Mrokow.
Yirmiya
R
R
Liebeskind
J C
JC
D000698:Analgesia; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D001921:Brain / Q000502:physiology*; D003433:Crosses, Genetic; D051379:Mice; D008810:Mice, Inbred C57BL / Q000502:physiology; D008815:Mice, Inbred Strains / Q000502:physiology*; D009043:Motor Activity; D009270:Naloxone / Q000494:pharmacology; D011957:Receptors, Opioid / Q000502:physiology*; D013045:Species Specificity; D013550:Swimming
D011957:Receptors, Opioid; D009270:Naloxone