Morphine administration in the amygdala or periaqueductal central gray depress serum levels of luteinizing hormone.
The ability of morphine to depress serum levels of luteinizing hormone (LH) directly at extra-hypothalamic sites was examined in male rats with guide cannulae implanted bilaterally in either the amygdala or the periaqueductal central gray (PAG). While no alterations in serum levels of LH in blood sampled via a chronic jugular catheter were observed following the microinjection of morphine, naloxone or artificial CSF in the amygdala or the PAG of intact males, serum levels of LH were significantly depressed in castrated rats following intracranial administration of morphine bilaterally in the cortical amygdala or the PAG. The intracranial administration of naloxone bilaterally in the PG likewise significantly elevated serum levels of LH in castrated rats. These data further establish the amygdala and the PAG as extrahypothalamic sites which can directly mediate the opiate-induced effects on LH.
D000679:Amygdala / Q000502:physiology*; D000818:Animals; D001921:Brain / Q000502:physiology*; D002555:Cerebrospinal Fluid / Q000502:physiology; D007700:Kinetics; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D009270:Naloxone; D009020:Morphine; D007986:Luteinizing Hormone