Depressor effect of closed-loop chip system in spontaneously hypertensive rats.
We previously reported that a closed-loop chip system was designed to decrease arterial pressure in normal rabbits and rats. In the present study, the depressor effects of the chip system were investigated in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). The arterial pressure was recorded, sampled, operated and processed in the chip system. The chip system instantaneously controlled arterial pressure by stimulating the left aortic depressor nerve according to the feedback signals of arterial pressure. The closed-loop chip system effectively decreased mean arterial pressure (MAP) and heart rate (HR) in both SHR and WKY rats. It decreased the duration and the maximal MAP level of the pressor response evoked by either intravenous injection of phenylephrine or cutaneous nociceptive stimulation in SHR, but had no significant effect on the magnitude of the increase in MAP. Furthermore, the chip system significantly increased the baroreflex gain in SHR, but not in normal WKY rats. These results suggest that the closed-loop chip system effectively decreases the arterial pressure and increases baroreflex gain in SHR. The chip system does not abolish the arterial pressure responses to accidental pressor events, but decreases the duration and the maximal MAP level of the pressor responses.
Gao
Xing-Ya
XY
Department of Physiology, Nanjing Medical University, Nanjing 210029, China.
Huang
Xing-Lin
XL
Wang
Han-Jun
HJ
Zhou
Li-Min
LM
Xu
Yao
Y
Wang
Wei
W
Zhu
Guo-Qing
GQ
D000818:Animals; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D004558:Electric Stimulation / Q000379:methods*; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D008838:Microcomputers; D010656:Phenylephrine / Q000494:pharmacology; D010812:Physical Stimulation / Q000379:methods; D011312:Pressure; D051381:Rats; D011918:Rats, Inbred SHR / Q000502:physiology*; D011921:Rats, Inbred WKY; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D010656:Phenylephrine