Issue Archive

The Responses of phrenic diecharges to microinjection of morphine and naloxone into central nucleus amygdala of rabbits

Nie Lin, Lui Lei

Department of Physiology, Shanglong Medical University. Jinan 250012, China

Abstract

Experiments were done on 24 urethan anesthetized (20%, 1g/kg)，vagatomized and spontaneously breathing rabbits (2-3 kg).The effects on phrenic activity by microinjection of morphine and naloxone into central nucleus amygdala (ACE) were observed. The main results were as follows:(I)Injection of morphine resulted in two res piratory effects，firstly a marked increase in inspiratory time[T_(1)]and amplitude of phrenic activity (AMP) with little changes of respiratory frequency (RF)，and second ly a singificant decrease in AMP with little changes in T_(1), (2) Injection of naloxone resulted in increases in RF，AMP and decreases in T_(1) with no marked changes in blood pressure.(3) Prolongation of inspiratory time by morphine can be blocked by previous injection of naloxone.The results suggested that endogenous morphine in ACE have different effects on respiration mediated by different receptor.

Key words: Central nucleus amygdala;Morphine;Naloxone;Phrenic activity

Received: 　　Accepted:

Corresponding author: 　　E-mail:

Citing This Article：

Nie Lin, Lui Lei. The Responses of phrenic diecharges to microinjection of morphine and naloxone into central nucleus amygdala of rabbits. Acta Physiol Sin 1993; 45 (1): (in Chinese with English abstract).