Role of nitric oxide in systemic effect of theophylline on mouse body temperature.
In the present study, the interaction of nitric oxide synthase (NOS) inhibitors, L-NAME (N(G)-nitro-L-arginine methyl ester HCl) and L-NA (N(omega)-nitro-L-arginine), and its precursor, L-arginine (2-(S)-2-amino-5-[(aminoiminomethyl)amino] pentatonic acid), with theophylline on mouse body temperature was studied. Intraperitoneal (i.p.) injection of different doses of theophylline altered body temperature. Lower doses of theophylline (12.5 and 25 mg/kg) increased, but a higher dose (100 mg/kg) reduced, the animals' body temperature. The combination of L-arginine (20 and 40 mg/kg) with the highest dose of theophylline potentiated the hypothermic effect induced by the latter drug, while L-arginine by itself did not alter body temperature. L-NAME (10-80 mg/kg) or L-NA (10 mg/kg) plus a lower dose of theophylline (12.5 mg/kg) reduced the theophylline-induced hyperthermic response. L-NA (1, 5, and 10 mg/kg) in combination with the high dose of theophylline (100 mg/kg) also induced greater hypothermia. Both L-NAME and L-NA by themselves reduced body temperature. It is concluded that nitric oxide (NO) may be involved in the effects of theophylline on body temperature in mice.
Zarrindast
Mohammad-Reza
MR
Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, PO Box 13145-784, Tehran, Iran. zarinmr@ams.ac.ir
Adl
Mohammad
M
Sharifzadeh
Mohammad
M
Bahreini
Taraneh
T
D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D001831:Body Temperature / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D008297:Male; D051379:Mice; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D013806:Theophylline / Q000494:pharmacology*
D009569:Nitric Oxide; D001120:Arginine; D013806:Theophylline; D019331:NG-Nitroarginine Methyl Ester