31P MRS of tumour metabolism in anaesthetized vs conscious mice.
The injectable anaesthetics Hypnorm/Hypnovel, chloral hydrate and etomidate, were examined for their effects on C3H/He mouse core temperature and on the in vivo 31P MR spectra of KHT and SCCVII/Ha transplantable tumours, compared with conscious mice gently restrained in jigs. Hypnorm/Hypnovel at 0.1 mL/mouse i.p. reduced core temperature by 6 degrees C at 30 min after injection, returning to control levels by 100 min, but did not significantly alter the 31P MR spectra of either KHT or SCCVII/Ha tumours. Chloral hydrate at 300 mg/kg i.p. produced a 5 degrees C fall in mouse core temperature, at 25 min after injection, again returning to control levels by 100 min. This agent increased the Pi/total ratio to 155% of control at 15 min after injection in the KHT tumour, and to 170% of control at 45 min in SCCVII/Ha. Etomidate at 25 mg/kg i.p. reduced mouse core temperature by 7.5 degrees C by 20 min after injection, returning to only 84% of control by 100 min. This agent increased the Pi/total ratio by 260% in the KHT tumour 15 min after injection, without recovery to control values by 100 min. In SCCVII/Ha, a maximum increase in Pi/total of 360% was observed at 15 min after injection, with a return to control levels by 60 min. In addition, etomidate caused convulsions in the mice during the induction phase, and myoclonic jerking within 15 min of anaesthesia.
Sansom
J M
JM
MRC Radiobiology Unit, Didcot, Oxon, UK.
Wood
P J
PJ
D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D002277:Carcinoma / Q000378:metabolism; D003243:Consciousness; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000378:metabolism*; D010758:Phosphorus; D012513:Sarcoma, Experimental / Q000378:metabolism
D000777:Anesthetics; D010758:Phosphorus