ISSN:
1432-2072
Keywords:
Lithium
;
5-Hydroxytryptamine
;
5-HT1 receptor
;
8-OH-DPAT
;
P-Chlorophenylanine
;
5-HT-mediated behaviour
;
Rat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Administration of lithium chloride (10 mmol/kg on day 1 and 3 mmol/kg twice daily on subsequent days, SC) for 3–14 days enhances the components of the serotonin syndrome produced by 8-hydroxy-2-(di-propylamino)tetralin (8-OH-DPAT) in the rat. The hypothermic response produced simultaneously was unaltered. Following lithium administration for 3 days the motor response to 5-methoxy,N,N-dimethyltryptamine was also facilitated. These data suggest that lithium administration enhances post-synaptic 5-HT receptor-mediated behavioural responses. (−)-Propranolol (20 mg/kg, IP) but not (+)-propranolol (20 mg/kg IP) fully antagonised the facilitated response to 8-OH-DPAT seen following lithium administration; ritanserin (200 μg/kg, IP) was without effect. These findings favour a mechanism for the action of lithium involving the 5-HT1A receptor. Depletion of 5-hydroxytryptamine (5-HT) with parachlorophenylalanine (PCPA, 300 mg/kg, IP on day 1 and 2 of lithium administration) did not prevent the facilitation by lithium of the response to 8-OH-DPAT. These data strengthen the suggestion that lithium has its effect on 5-HT1A-mediated motor function by a post-synaptic action. By contrast, motor responses to the putative 5-HT1B receptor agonist 5-methoxy-3-(1,2,3,6-tetrahydro-pyridin-4-yl)-1H-indole (RU 24969) were unaltered by repeated lithium administration.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00174066
