Effects of chronic systemic administration of opioid peptides, naloxone and N-acetyl beta-endorphin antiserum on gonadotropins and testicular functions in the rat.
Systemic administration of opioid peptides, methionine-enkephalin and beta-endorphin, chronically, lowered gonadotropin levels in plasma and had an inhibitory effect mainly on the testicular enzymes hyaluronidase, acid phosphatase and on incorporation of 3[H] thymidine in the tissue. When rats were similarly treated with opioid peptide antagonist naloxone and N-acetyl beta-endorphin antiserum, induced an opposite effect. This is either the direct effect of opioid peptides/antagonist on the gonads or it may be via the circulating levels of gonadotropin.
Laxmi
N A
NA
Dairy Cattle Physiology Division, National Dairy Research Institute, Karnal, India.
Vijayan
E
E
D000818:Animals; D004305:Dose-Response Relationship, Drug; D008297:Male; D009270:Naloxone / Q000008:administration & dosage* / Q000494:pharmacology; D018847:Opioid Peptides / Q000008:administration & dosage* / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013737:Testis / Q000187:drug effects* / Q000502:physiology; D001615:beta-Endorphin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology
D018847:Opioid Peptides; D009270:Naloxone; D001615:beta-Endorphin; C035101:N-acetyl-beta-endorphin