[The influence of serotonin on cochlear microcirculation].
OBJECTIVE
The present study was undertaken to investigate the influence of serotonin (5-HT) on cochlear microcirculation.


METHODS
2 microliters 0.5% 5-HT were applied to round window membrane in anaesthetized guinea pigs. The three parameters as blood flow (CBF), number of blood cell moving (CMBC) and blood velocity (Veloc) of cochlear microcirculation were measured with laser doppler flowmeter. The mean arterial pressure (MABP) was recorded simultaneously.


RESULTS
5-HT induced a biphasic response of reduction in cochlear blood flow. In the first phase, cochlear microcirculation showed a transient abruptly reduction. The CBF, CMBC and Veloc reached to 86.8%, 90.2% and 96.3% of the baseline respectively. The second phase reduced slowly. The CBF and CMBC decreased to 89.7% and 89.6% by average throughout the experiment period respectively. The Veloc and MABP had no significant changes.


CONCLUSIONS
5-HT could decrease the cochlear, blood flow and result in cochlear microcirculation dysfunction.
Luo
Z Q
ZQ
Department of Otolaryngology, Union Hospital, Tongji Medical University, Wuhan 430022.
Kong
W J
WJ
D000818:Animals; D003051:Cochlea / Q000098:blood supply*; D006168:Guinea Pigs; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation / Q000187:drug effects; D012701:Serotonin / Q000494:pharmacology*
D012701:Serotonin