Effects of long-term administration of clenbuterol in mature female rats.
Female Sprague-Dawley rats were treated IM with 0, 2.5, 25, and 50 micrograms of clenbuterol HCl/kg of body weight/d for 21 days. In all treated rats, significant increase in body weight gain (P < 0.05) and improvement in feed conversion ratio (P < 0.05) were recorded. Hydrometra was observed in the uterus of treated rats, and histologically, it was possible to see dilatation of luminal glands and ovarian alterations. Clenbuterol treatment induced significant (P < 0.05) increase in uterine estrogen receptor concentration of rats treated with the 2 higher doses. Treatment apparently failed to enhance the rate of oxidative and conjugative biotransformations, except for glucuronidation of p-nitrophenol (P < 0.05). On the basis of the data obtained, we could affirm that high doses of clenbuterol affect the female reproductive system of rats inducing, almost in part, estrogen-like modifications, but probably by a different mechanism of action correlated to intense adrenergic stimulation.
Department of Animal Pathology, University of Torino, Italy.
G
G
Re
P
P
Badino
M
M
Dacasto
C
C
Nebbia
B
B
Biolatti
F
F
Di Carlo
C
C
Girardi
D015660:7-Alkoxycoumarin O-Dealkylase / Q000378:metabolism; D000815:Aniline Hydroxylase / Q000378:metabolism; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002976:Clenbuterol / Q000008:administration & dosage / Q000494:pharmacology*; D019363:Cytochrome P-450 CYP1A1; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D003600:Cytosol / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004958:Estradiol / Q000097:blood / Q000378:metabolism; D005260:Female; D014453:Glucuronosyltransferase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology; D010088:Oxidoreductases / Q000378:metabolism; D011282:Pregnenediones / Q000378:metabolism; D011374:Progesterone / Q000097:blood; D045167:Progesterone Congeners / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism; D011980:Receptors, Progesterone / Q000187:drug effects / Q000378:metabolism; D014599:Uterus / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D015430:Weight Gain
D011282:Pregnenediones; D045167:Progesterone Congeners; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C020175:16 alpha-ethyl-21-hydroxy-19-nor-4-pregnene-3,20-dione; D011374:Progesterone; D004958:Estradiol; D003577:Cytochrome P-450 Enzyme System; D010088:Oxidoreductases; D015660:7-Alkoxycoumarin O-Dealkylase; D000815:Aniline Hydroxylase; D019363:Cytochrome P-450 CYP1A1; D014453:Glucuronosyltransferase; D005982:Glutathione Transferase; D002976:Clenbuterol