ISSN:
1435-1463
Keywords:
Galanin
;
galanin fragments
;
behavior
;
analgesia
;
rat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Behavioral effect of galanin and its fragments, galanin1–15 and galanin16–29 (200 ng, 1 and 5 μg), after intracerebroventricular (i.c.v.) administration was studied in rats. The number of crossings and pippings and the time of locomotion (an open field test) showed a similar sedative action of galanin and galanin16–29, with no significant effect of galanin1–15. Galanin and its fragments, injected in doses of 200 ng, 1 and 5 μg, did not affect nociception, as measured by a tail-flick and paw pressure test. Galanin and galanin1–15, but not galanin16–29 (5 μg i.c.v.), injected together with morphine (2.5 μg i.c.v.), significantly potentiated the analgetic effect of morphine assessed by a paw pressure test; a similar tendency was also observed in a tail-flick test. Galanin and its two fragments injected in doses of 200 ng, 1 and 5 μg, did not change the effect of morphine given in a dose of 1 μg. These data suggest that galanin, having no effect when given alone, potentiate the analgetic effect of morphine. The fact that the N-terminal fragment of galanin acts like a natural peptide suggests a receptor mediated action. In conclusion, the analgesic effect of morphine was potentiated by galanin and its N-terminal fragment galanin1–15. On the other hand, behavioral study showed a similar sedative action of galanin and C-terminal fragment galanin16–29. This suggests that the N- and C-terminal fragments of galanin are differentially involved in behavioral effects of the peptide.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01281157
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