RESUMO
Three-hour infusions of angiotensin II (ANG II) agonists and antagonists were used to determine the relative sites of action of ANG in producing water drinking and salt appetite. In the first experiment, lateral ventricular (LV) but not fourth ventricular (4V) ANG II elicited water and saline intake, and LV but not 4V sarile, a competitive ANG II receptor blocker, reduced saline intake aroused by ip injections of 10 mg/kg furosemide and 6 mg/kg captopril. In the second experiment, water, but not saline, intake to furosemide-captopril treatment was reduced by sarile infusions into the subfornical organ (SFO). It is concluded that (a) brain ANG receptors for water and saline intakes are more accessible from the forebrain than the hindbrain ventricles and (b) receptors for water drinking, but not saline intake, after captopril reside in part in the SFO. Salt appetite appears to be dependent on ANG II receptors somewhere in the forebrain other than in the SFO.
Assuntos
Angiotensina II/farmacologia , Apetite/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Captopril/farmacologia , Ingestão de Líquidos/efeitos dos fármacos , Sódio na Dieta/administração & dosagem , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Angiotensina II/análogos & derivados , Animais , Inibidores Enzimáticos/farmacologia , Furosemida/farmacologia , Injeções Intraventriculares , Masculino , Ratos , Ratos Endogâmicos , Órgão Subfornical/efeitos dos fármacosRESUMO
These experiments were conducted to test whether drinking to ip captopril or to intraventricular carbachol requires an intact fiber system from the ventral subfornical organ (SFO). Wire-knife cuts were made through the wall of the third ventricle ventral to the SFO. Control rats had either sham lesions or histologically identified missed cuts. Rats with good cuts (a) drank less than either control group after ip injections of 4 mg/kg captopril, (b) drank normal amounts of 0.3 M NaCl solution when captopril was placed in the drinking water at 0.1 mg/ml, (c) drank less water but a normal amount of saline after 6 mg/kg captopril ip and 10 mg/kg furosemide diuretic ip, and (d) drank normal amounts of water after lateral ventricular injections of 1.2 or 4 nmol of carbachol. The results of the captopril experiments confirm predictions based on studies of SFO lesions and suggest that captopril causes water, but not saline, drinking via an angiotensin-related mechanism acting at the SFO. The carbachol experiment indicates either that the SFO is not a unique receptor site for ventricular carbachol or that the fibers mediating this response do not require the pathways through the ventral pole of the SFO.
Assuntos
Captopril/farmacologia , Carbacol/farmacologia , Ingestão de Líquidos/efeitos dos fármacos , Sistemas Neurossecretores/efeitos dos fármacos , Órgão Subfornical/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Mapeamento Encefálico , Ventrículos Cerebrais/efeitos dos fármacos , Furosemida/farmacologia , Injeções Intraventriculares , Masculino , Vias Neurais/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Equilíbrio Hidroeletrolítico/efeitos dos fármacosRESUMO
Two experiments were designed to test whether angiotensin (ANG) synthesis or receptor activation in the ventral preoptic region is critical for ANG-induced salt appetite in rats. In Experiment 1, infusions of ANG into the subfornical organ (SFO) produced water drinking without saline intake, but infusions near the organum vasculosum laminae terminalis (OVLT) produced both water and saline drinking. Thus, forebrain areas that support water drinking to ANG do not all support salt appetite. In Experiment 2, rats were given oral captopril (CAP) to enhance daily intake of water and saline solution by increasing ANG II synthesis in the brain. CAP microinjected into the SFO reduced CAP-enhanced water drinking without affecting saline intake, but CAP in the OVLT reduced enhanced saline intake without affecting water drinking. Thus, ANG acting in the OVLT, the most ventral part of the median preoptic nucleus, or other nearby structures is important for ANG-induced salt appetite.
Assuntos
Angiotensina II/fisiologia , Apetite/fisiologia , Área Pré-Óptica/fisiologia , Receptores de Angiotensina/fisiologia , Sódio na Dieta , Animais , Mapeamento Encefálico , Ventrículos Cerebrais/fisiologia , Ingestão de Líquidos/fisiologia , Masculino , Ratos , Ratos Endogâmicos , Órgão Subfornical/fisiologia , Equilíbrio Hidroeletrolítico/fisiologiaRESUMO
OBJECTIVES: To determine the long-term success rate for the modified Pereyra bladder neck suspension and to identify preoperative characteristics that create differences in surgical outcome. We attempted retrospectively to separate those patients with what we now recognize was significant intrinsic sphincter deficiency (ISD) before routine use of Valsalva leak point pressures (VLPPs) was available. METHODS: The charts and videourodynamic reports of 208 patients who underwent a modified Pereyra bladder neck suspension from June 1988 to June 1996 were reviewed, and survey questionnaires were mailed to all patients. All videourodynamic study reports and charts were reviewed to identify those with what we now recognize was significant ISD and compare them with a group that we believed had more pure descent problems. RESULTS: A total of 135 patients or 65% of the population responded. The mean time after surgery was 4.14 years. At the follow-up survey, 14% reported no leakage at all, 42% reported very little or mild leakage, 38% reported moderate leakage, and 6% reported severe leakage. Fifty-three percent of patients continued to wear pads. Seventy-nine percent reported improvement in their leakage compared with the preoperative state, and 69% were satisfied with the results. When patients with preoperative ISD were compared with patients with pure bladder neck hypermobility, the ISD group had more leakage and less improvement after surgery than patients with bladder neck hypermobility. CONCLUSIONS: With an average follow-up of greater than 4 years, most women continued to leak with symptoms of stress urinary incontinence. Even though 79% reported improvement over their preoperative condition and 69% were satisfied, the results were disappointing. Patients with significant ISD had a worse outcome (2.6% dry) than patients with pure bladder neck hypermobility (20% dry). Given the above data, significant ISD is a contraindication for a modified Pereyra transvaginal needle suspension, and these data cast further doubt on the ability of the modified Pereyra needle suspension to consistently cure even anatomic incontinence.