On the presence of a MSH-release inhibiting system in the rat neurointermediate lobe.
Rat neurointermediate lobes were superfused in vitro and showed a stable secretion rate of MSH after 30 min. MSH secretion from lobes of untreated rats was reversibly inhibited during superfusion with medium containing 45 mM K+. This inhibition could not be induced using lobes from median eminence lesioned or reserpinized rats. Superfusion with 45 mM K+ also induced release of dopamine from lobes preincubated with the labeled transmitter. It is concluded that the MSH-release inhibiting system present in the rat neurointermediate lobe may be identical to the dopaminergic arcuate-intermediate lobe system.
D000818:Animals; D001681:Biological Assay; D003919:Diabetes Insipidus / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D005260:Female; D007031:Hypothalamus / Q000502:physiology / Q000503:physiopathology; D009075:MSH Release-Inhibiting Hormone / Q000378:metabolism*; D008473:Median Eminence / Q000187:drug effects / Q000378:metabolism; D010477:Perfusion; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D013997:Time Factors
D012110:Reserpine; D009075:MSH Release-Inhibiting Hormone; D011188:Potassium; D004298:Dopamine