title: Pharmacological characterization of the magnocellular neuroendocrine cells of the guinea pig supraoptic nucleus in vitro.
abstract: The effects of various agents which have been implicated in the regulation of vasopressin release, on the supraoptic neuroendocrine cells were studied intracellularly. L-glutamate (10(-4)M) and gamma-aminobutyric acid (10(-6) M) had potent excitatory and inhibitory actions, respectively. Acetylcholine (10(-6) M) depolarized the membrane and increased the membrane input resistance. Norepinephrine (10(-5) M) produced either excitatory or inhibitory action on the spontaneous firing rate depending on the cell impaled. Morphine (10(-8)-10(-6) M) strongly depressed the spontaneous firing rate whereas it has no noticeable effect on the membrane potential and input resistance. Angiotensin II (10(-5) M) had no effect on any of the cells tested.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D005998:Glycine / Q000494:pharmacology; D006168:Guinea Pigs; D009020:Morphine / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D012970:Sodium Glutamate / Q000494:pharmacology; D013495:Supraoptic Nucleus / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
chemical_list: D000804:Angiotensin II; D005680:gamma-Aminobutyric Acid; D009020:Morphine; D000109:Acetylcholine; D005998:Glycine; D012970:Sodium Glutamate; D009638:Norepinephrine