Lateral hypothalamic region excites the activity of vasopressin neurons in the supraoptic nucleus through subfornical organ neurons.
In urethane-anesthetized male rats, microinjection of angiotensin II into the lateral hypothalamic area excited the activity of about half (N = 7) of subfornical organ neurons (N = 15) antidromically identified as projecting to the hypothalamic supraoptic nucleus. Microinjection of angiotensin II also excited the activity of approximately one-quarter (N = 8) of putative vasopressin-secreting neurons (N = 28) in the hypothalamic supraoptic nucleus and these excitatory responses of putative vasopressin-secreting neurons were blocked (N = 3) or attenuated (N = 3) by pretreatment with the angiotensin II antagonist saralasin, but not by isotonic saline (N = 2), in the subfornical organ.
D000200:Action Potentials / Q000187:drug effects; D000804:Angiotensin II / Q000502:physiology; D000818:Animals; D007026:Hypothalamic Area, Lateral / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000502:physiology; D009490:Neurosecretory Systems / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012504:Saralasin / Q000494:pharmacology; D013356:Subfornical Organ / Q000187:drug effects / Q000502:physiology*; D013495:Supraoptic Nucleus / Q000187:drug effects / Q000502:physiology*; D014667:Vasopressins / Q000502:physiology*
D014667:Vasopressins; D000804:Angiotensin II; D012504:Saralasin