Cholecystokinin actions in the parabrachial nucleus: effects on thirst and salt appetite.
The present study investigated the effects of bilateral injections of the nonselective CCK receptor antagonist proglumide or CCK-8 into the lateral parabrachial nuclei (LPBN) on the ingestion of 0.3 M NaCl and water induced by intracerebroventricular injection of ANG II or by a combined treatment with subcutaneous furosemide (Furo) + captopril (Cap). Compared with the injection of saline (vehicle), bilateral LPBN injections of proglumide (50 micrograms . 200 nl-1 . site-1) increased the intake of 0.3 M NaCl induced by intracerebroventricular ANG II (50 ng/1 microliter). Bilateral injections of proglumide into the LPBN also increased ANG II-induced water intake when NaCl was simultaneously available, but not when only water was present. Similarly, the ingestion of 0.3 M NaCl and water induced by the treatment with Furo (10 mg/kg) + Cap (5 mg/kg) was increased by bilateral LPBN proglumide pretreatment. Bilateral CCK-8 (0.5 microgram . 200 nl-1 . site-1) injections into the LPBN did not change Furo + Cap-induced 0.3 M NaCl intake but reduced water consumption. When only water was available after intracerebroventricular ANG II, bilateral LPBN injections of proglumide or CCK-8 had no effect or significantly reduced water intake compared with LPBN vehicle-treated rats. Taken together, these results suggest that CCK actions in the LPBN play a modulatory role on the control of NaCl and water intake induced by experimental treatments that induce hypovolemia and/or hypotension or that mimic those states.
Menani
J V
JV
Departamento de Ciências Fisiológicas, Faculdade de Odontologia, Paulista State University, Araraquara, São Paulo 14801-903, Brazil.
Johnson
A K
AK
D000818:Animals; D001066:Appetite / Q000502:physiology*; D001067:Appetite Depressants / Q000008:administration & dosage; D002766:Cholecystokinin / Q000037:antagonists & inhibitors / Q000502:physiology*; D007276:Injections, Intraventricular; D008297:Male; D011377:Proglumide / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors / Q000502:physiology; D012249:Rhombencephalon / Q000187:drug effects / Q000502:physiology*; D012844:Sincalide / Q000008:administration & dosage; D012965:Sodium Chloride; D014867:Water
D001067:Appetite Depressants; D011949:Receptors, Cholecystokinin; D014867:Water; D012965:Sodium Chloride; D002766:Cholecystokinin; D011377:Proglumide; D012844:Sincalide