[45Ca-uptake, mitochondrial protein bound Ca2+ and ultrastructural distribution of Ca2+ in some brain regions of mice during drug-induced analgesia].
After buprenorphine (Bup, 0.8 mg/kg ip) treatment 45Ca-uptake (cpm/mg fresh brain) in vivo by brain slices decreased from 589 +/- 12 and 486 +/- 12 to 522 +/- 14 and 408 +/- 10 and mitochondrial protein bound Tb3+ (Tb3+ relative fluorescent intensity) reduced from 41 +/- 5 and 32 +/- 2 to 30 +/- 3 and 22 +/- 2 in periaqueductal grey and hypothalamus, respectively. A large amount dense precipitate occurred in the myelin sheath and mitochondria in both regions. The 45Ca-uptake evoked by buprenorphine at 16 micrograms/40 microliter in vitro has the similar tendency with that in vivo. Treated by ruthenium red (20 micrograms/mouse ip or icv) before buprenorphine, the above-mentioned effects were all abolished. Similar results were obtained with morphine (Mor, 10 mg/kg ip) and verapamil (Ver, 8 micrograms/mouse icv) instead of buprenorphine and ruthenium red, respectively. These results suggest that Ca2+ transport across neuroplasmic membranes plays a mediator role in drug-induced analgesia.
Division of Physiology, Nanjing University, China.
X N
XN
Zhao
Z X
ZX
Zhang
S L
SL
Shi
X G
XG
Wang
A Z
AZ
Yang
T L
TL
Wang
W F
WF
Zhao
M J
MJ
Huang
R S
RS
Chen
D000700:Analgesics; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002047:Buprenorphine / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism / Q000493:pharmacokinetics*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D005260:Female; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000378:metabolism*; D009020:Morphine / Q000494:pharmacology; D009186:Myelin Sheath / Q000378:metabolism; D012430:Ruthenium Red / Q000494:pharmacology
D000700:Analgesics; D002135:Calcium-Binding Proteins; D012430:Ruthenium Red; D002047:Buprenorphine; D009020:Morphine; D002118:Calcium