Nitroester drug's effects and their antagonistic effects against morphine on human sphincter of Oddi motility.
OBJECTIVE
To evaluate the effects of nitroester drugs on human sphincter of Oddi (SO) motility and their antagonistic effects against morphine which shows excitatory effect on Oddi's sphincter motility.


METHODS
The effects of these drugs on SO were evaluated by means of choledochofiberoscopy manometry. A total of 67 patients having T-tubes after cholecystectomy and choledochotomy were involved in the study, they were randomly divided into glyceryl trinitrate (GTN) group, isosorbide dinitrate (ISDN) group, pentaerythritol tetranitrate (PTN) group, morphine associated with GTN group, morphine associated with ISDN group and morphine associated with PTN group. Basal pressure of Oddi's sphincter (BPOS), amplitude of phasic contractions (SOCA), frequency of phasic contractions (SOF), duration of phasic contractions (SOD), duodenal pressure (DP) and common bile duct pressure (CBDP) were scored and analyzed. Morphine was given intramuscularly while nitroester drugs were applied sublingually.


RESULTS
BPOS and SOCA decreased significantly after administration of ISDN and GTN, BPOS reduced from 10.95+/-7.49 mmHg to 5.92+/-4.04 mmHg (P<0.05) evidently after application of PTN. BPOS increased from 7.37+/-5.58 mmHg to 16.60+/-13.87 mmHg, SOCA increased from 54.09+/-38.37 mmHg to 100.70+/-43.51 mmHg, SOF increased from 7.15+/-3.20 mmHg to 10.38+/-2.93 mmHg and CBDP increased 3.75+/-1.95 mmHg to 10.49+/-8.21 mmHg (P<0.01) evidently after injection of morphine. After associated application of ISDN and GTN, the four indications above decreased obviously. As for application associated with PTN, SOCA and SOF decreased separately from 100.64+/-44.99 mmHg to 66.17+/-35.88 mmHg and from 10.70+/-2.76 mmHg to 9.04+/-1.71 mmHg (P<0.05) markedly.


CONCLUSIONS
The regular dose of GTN, ISDN and PTN showed inhibitory effect on SO motility, morphine showed excitatory effect on SO while GTN, ISDN and PTN could antagonize the effect of morphine. Among the three nitroester drugs, the effect of ISDN on SO was most significant.
Wu
Shuo-Dong
SD
Department of Hepatobiliary Surgery, the Second Affiliated Hospital, China Medical University, Shenyang 110004, Liaoning Province, China. wushuodong@hotmail.com
Zhang
Zhen-Hai
ZH
Li
Dong-Yan
DY
Jin
Jun-Zhe
JZ
Kong
Jing
J
Tian
Zhong
Z
Wang
Wei
W
Wang
Min-Fei
MF
D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D004347:Drug Interactions; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage*; D005996:Nitroglycerin / Q000008:administration & dosage*; D010417:Pentaerythritol Tetranitrate / Q000008:administration & dosage; D009803:Sphincter of Oddi / Q000187:drug effects* / Q000502:physiology; D014665:Vasodilator Agents / Q000008:administration & dosage*
D000701:Analgesics, Opioid; D014665:Vasodilator Agents; D010417:Pentaerythritol Tetranitrate; D009020:Morphine; D005996:Nitroglycerin; D007548:Isosorbide Dinitrate