Stimulation of prolactin secretion by L-3,4-dihydroxyphenyl-serine (L-DOPS) via central norepinephrine in the rat.
Intracerebroventricular (icv) injection of L-3,4-dihydroxyphenylserine (L-DOPS) (50 and 250 micrograms/rat) raised in a dose-related manner both plasma prolactin (PRL) and CSF norepinephrine (NE) in urethane-anesthetized male rats. Intravenous (iv) injection of larger doses of L-DOPS (5 and 10 mg/100 g BW) slightly but significantly increased plasma PRL and CSF NE. L-DOPS injection (50 micrograms/rat, icv or 5 mg/100 g BW, iv) also raised plasma PRL in conscious rats. There was a good correlation (r = 0.74) between CSF NE and peak plasma PRL in the anesthetized animals. Propranolol (100 micrograms/100 g BW, iv) inhibited plasma PRL responses to L-DOPS (50 micrograms/rat, icv) and NE injection (1 microgram/rat, icv) raised plasma PRL in anesthetized animals. These findings indicate that L-DOPS stimulates PRL secretion via central noradrenergic mechanisms in the rat.
D000818:Animals; D003243:Consciousness; D015103:Droxidopa / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D009638:Norepinephrine / Q000134:cerebrospinal fluid / Q000502:physiology*; D011388:Prolactin / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D011388:Prolactin; D011433:Propranolol; D015103:Droxidopa; D009638:Norepinephrine