Post-synaptic changes and increased dopamine receptor sensitivity in hypothyroid rats.
Hypothyroid rats showed increased behavioral sensitivity to both selective and non-selective dopamine agonists. Ligand binding analysis revealed no differences in concentration or affinity of striatal dopamine receptor subtypes in hypothyroid rats. Measurement of striatal cAMP levels however, indicated that hypothyroid rats showed a greater increase in cAMP production in response to stimulation by dopamine. It is concluded that the changes in behavioural sensitivity observed may be associated with alterations in post-synaptic mechanisms.
Cameron
D L
DL
Department of Clinical Pharmacology, School of Medicine, Flinders University of South Australia, Bedford Park, Adelaide.
Crocker
A D
AD
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000503:physiopathology; D000242:Cyclic AMP / Q000378:metabolism; D004298:Dopamine / Q000494:pharmacology; D004873:Ergolines / Q000494:pharmacology; D007037:Hypothyroidism / Q000503:physiopathology*; D008297:Male; D011441:Propylthiouracil / Q000494:pharmacology; D019257:Quinpirole; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000502:physiology*; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2
D001552:Benzazepines; D004873:Ergolines; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D019257:Quinpirole; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D011441:Propylthiouracil; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D001058:Apomorphine; D004298:Dopamine