Abstract
Although d- and l-amphetamine had no effect on plasma prolactin levels in untreated male rats, both d- and l-amphetamine reversed the increase in plasma prolactin levels produced by reserpine and 5-hydroxytryptophan (5-HTP). Only d-amphetamine significantly reversed the effect of alpha-methylparatyrosine (AMPT) on plasma prolactin levels. This reversal is probably due to a direct or indirect dopamine agonist effect of amphetamine, rather than to an effect on norepinephrine. This conclusion is based on the finding that apomorphine, a direct-acting dopamine agonist, reversed the reserpine-induced increase in prolactin secretion, while clonidine, a direct-acting alpha-adrenergic agonist, potentiated the reserpine-induced stimulation of prolactin secretion. The effect of d-amphetamine on the increase in plasma prolactin levels produced by reserpine, 5-HTP, or AMPT was always greater than that of the l-isomer, suggesting that the d-isomer has a more profound effect on dopaminerelease or neuronal reuptake, or both, than l-amphetamine. Chronic administration of d-amphetamine prior to reserpine did not inhibit the ability of d-amphetamine to reverse the reserpine-induced increase in plasma prolactin. Chronic administration of AMPT did not enhance the ability of d-amphetamine to reverse the AMPT-induced increase in plasma prolactin.
Original language | English (US) |
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Pages (from-to) | 63-69 |
Number of pages | 7 |
Journal | Psychopharmacology |
Volume | 61 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1 1979 |
Keywords
- 5-Hydroxytryptophan
- Alpha-methylparatyrosine
- Dopamine
- Prolactin
- Reserpine
- Supersensitivity
- Tolerance
- d-Amphetamine
- l-Amphetamine
ASJC Scopus subject areas
- Pharmacology