Effect of (-)-stepholidine on serum prolactin level of female rats.
OBJECTIVE
To study the effect of (-)-stepholidine (SPD) on serum prolactin (PRL) level and elucidate its pharmacological action on dopamine D2 receptors.


METHODS
After i.p. administration of dopamine receptor agonist, antagonist, or SPD, the serum PRL levels were determined by radioimmunoassay.


RESULTS
SPD (24 mg.kg-1, i.p.) caused a rapid rise in serum PRL level, lasting more than 1 h. SPD 0.2-40 mg.kg-1 raised serum PRL level in a dose-dependent manner with ED50 of 3.7 mg.kg-1 (95% confidence limits, 2.6-4.3 mg.kg-1) and PRL maximal level of 448 +/- 64 micrograms.L-1. Pergolide 2 mg.kg-1 i.p. caused a decrease (P < 0.01 vs saline) of PRL level, which was partially attenuated by SPD of 5 mg.kg-1 and completely abolished by 10 mg.kg-1.


CONCLUSIONS
SPD is a dopamine D2 receptor antagonist.
Zou
L L
LL
Shanghai Institute of Materia Medica, Chinese Academy of Sciences, China.
Chen
Y
Y
Song
Y Y
YY
Jin
G Z
GZ
D000818:Animals; D001599:Berberine / Q000031:analogs & derivatives* / Q000494:pharmacology; D018491:Dopamine Agonists; D018492:Dopamine Antagonists / Q000494:pharmacology*; D065127:Dopamine D2 Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D005260:Female; D006220:Haloperidol / Q000494:pharmacology; D010479:Pergolide / Q000037:antagonists & inhibitors; D011388:Prolactin / Q000097:blood*; D051381:Rats; D017207:Rats, Sprague-Dawley
D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D065127:Dopamine D2 Receptor Antagonists; D001599:Berberine; C010513:stepholidine; D010479:Pergolide; D011388:Prolactin; D006220:Haloperidol