The effects of enalapril maleate and cold stress exposure on tyrosine hydroxylase activity in some rat tissues.
Enalapril is a highly specific and competitive inhibitor of angiotensin-I converting enzyme (ACE) and thus belongs to the category of ACE inhibitors. The beneficial effects of ACE inhibitors appear to result primarily from the suppression of the plasma renin-angiotensin-aldesterone system. This study was designed to detect the effects of enalapril maleate and cold stress on tyrosine hydroxylase (TH) activity in adrenal medulla, heart and hypothalamus in rat. In cold stress treatment (exposed to 8 degrees C cold for 48 h) TH activity was found to be raised significantly (p < 0.05) in adrenal medulla, hypothalamus and heart tissues. In the adrenal medulla, hypothalamus and heart tissues, TH activity of enalapril maleate treated rats (10 mg kg(-1) body weight) group was not raised significantly (p > 0.05). Following intraperitoneal injection of enalapril maleate (10 mg kg(-1) body weight) the rats were exposed to 8 degrees C cold for 48 h. After cold stress and enalapril maleate treatment no statistically significant change in tyrosine hydroxylase activity was detected in adrenal medulla, hypothalamus or heart (p > 0.05). The results of our studies show that enalapril maleate blocks the effect of cold stress on the regulation of TH activity.
Talas
Zeliha Selamoglu
ZS
Inonu University, Department of Molecular Biology, 44280 Campus Malatya, Turkey. ztalas@inonu.edu.tr
Yurekli
Muhittin
M
D000313:Adrenal Medulla / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D000818:Animals; D002395:Catecholamines / Q000494:pharmacology; D003080:Cold Temperature; D004656:Enalapril / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D007031:Hypothalamus / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D007274:Injections, Intraperitoneal; D051381:Rats; D011916:Rats, Inbred F344; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis / Q000187:drug effects / Q000378:metabolism*
D002395:Catecholamines; D004656:Enalapril; D014446:Tyrosine 3-Monooxygenase