Modification of the behavioural effects of haloperidol and of dopamine receptor regulation by altered thyroid status.

Abstract

Rats made hypothyroid by the chronic oral administration of 200 mg/kg propylthiouracil were less sensitive to the cataleptic effects of haloperidol (0.1 mg/kg) treatment than were euthyroid rats chronically treated with isotonic saline. However, rats made hyperthyroid by the chronic injection of 200 micrograms/kg thyroxine were not more sensitive to the cataleptic suppressant effects of haloperidol (0.1 mg/kg). Higher doses of haloperidol (1 and 5 mg/kg) produced significantly greater catalepsy in the hyperthyroid rats and significantly reduced catalepsy in the hypothyroid rats. Receptor binding studies carried out on the striata from rats sacrificed 48 h after a 6-day course of chronic haloperidol (0.1 mg/kg once daily) treatment revealed a significant upregulation (increase) of dopamine receptors in the hypothyroid rats only. These findings are consistent with the hypothesis that altered thyroid status can modify the sensitivity of dopamine receptors.

• Authors: A D Crocker, D H Overstreet
• Journal: Psychopharmacology (Psychopharmacology (Berl)) Vol. 82 Issue 1-2 Pg. 102-6 ( 1984) ISSN: 0033-3158 [Print] Germany
• PMID: 6420818 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Receptors, Dopamine
• Thyroid Hormones
• Spiperone
• Haloperidol

Topics

• Animals
• Behavior, Animal (drug effects)
• Body Temperature
• Catalepsy (chemically induced)
• Haloperidol (pharmacology)
• Humans
• Hyperthyroidism (psychology)
• Hypothyroidism (psychology)
• Male
• Rats
• Rats, Inbred Strains
• Receptors, Dopamine (drug effects)
• Spiperone (metabolism)
• Thyroid Hormones (physiology)