Differentiation of ketamine effects on renal nerve activity and renal blood flow in rats.
BACKGROUND
A biphasic pattern in the effects of increasing dose of ketamine on mean arterial blood pressure (MBP) and renal sympathetic nerve activities (RSNA) was shown in previous study. We hypothesized that if renal vascular resistance (RVR) and renal blood flow (RBF) are mainly controlled by RSNA, they will show a similar biphasic pattern under increasing doses of ketamine.


METHODS
16 female Wistar rats anesthetized with urethane were studied for ketamine at 0.5, 1, 2 mg/kg, i.v. at 30 min intervals. Multifiber RSNA recording was studied in 8 rats and RBF (by electromagnetic flowmeter) and RVR were studied in the other 8 rats with intact renal nerves.


RESULTS
Our results showed that although incremental doses of ketamine brought about a biphasic pattern in MBP and RSNA, the decrease in RBF and the increase in RVR went a dose-related way.


CONCLUSIONS
We concluded that there was a differentiation of ketamine effects on renal nerve activity and renal blood flow in rats. The changes of RBF and RVR can not only be attributed to the effects of sympathetic nerve activities.
Chien
Chiang-Ting
CT
Department ofAnesthesiology, National Taiwan University Hsopital, National Taiwan University, Taiwan, ROC.
Cheng
Ya-Jung
YJ
Chen
Chau-Fong
CF
Chen
Chien-Yu
CY
Lin
Chen-Jung
CJ
D000818:Animals; D004305:Dose-Response Relationship, Drug; D005260:Female; D007649:Ketamine / Q000494:pharmacology*; D007668:Kidney / Q000294:innervation*; D051381:Rats; D017208:Rats, Wistar; D012079:Renal Circulation / Q000187:drug effects*; D013564:Sympathetic Nervous System / Q000187:drug effects*; D014655:Vascular Resistance / Q000187:drug effects
D007649:Ketamine