Degeneration of capsaicin-sensitive sensory nerves leads to increased saltsensitivity through enhancement of sympathoexcitatory response

Citation
Dh. Wang et al., Degeneration of capsaicin-sensitive sensory nerves leads to increased saltsensitivity through enhancement of sympathoexcitatory response, HYPERTENSIO, 37(2), 2001, pp. 440-443
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
HYPERTENSION
ISSN journal
0194-911X → ACNP
Volume
37
Issue
2
Year of publication
2001
Part
2
Supplement
S
Pages
440 - 443
Database
ISI
SICI code
0194-911X(200102)37:2<440:DOCSNL>2.0.ZU;2-Z
Abstract
We have previously shown that neonatal degeneration of capsaicin-sensitive sensory nerves renders a rat responsive to a salt load with an increase in blood pressure and a decrease in natriuretic response. To test the hypothes is that the enhanced svmpathoexcitatory response to a high salt intake cont ributes to the development of hypertension in this model, newborn Wistar ra ts were given 50 mg/kg capsaicin and/or 80 mg/kg guanethidine subcutaneousl y. Control rats were treated with vehicle. After the weaning period, male r ats were grouped as the following and given a high sodium diet (4%) for 2 w eeks: capsaicin and guanethidine coadministration (CAP-GUA), capsaicin only (CAP), guanethidine only (CUA), and vehicle control (CON). Norepinephrine concentrations in the atrium were significantly lower in CAP-GUA and GUA th an in CON rats (P<0.05). Twenty-four-hour urine and sodium excretions were significantly lower in CAP than in CAP-GUA, GUA, and CON rats (P<0.05). Mea n arterial pressure (mm Hg) was significantly higher in CAP (180+/-10) than in CAP-GUA (106+/-1), GUA (133+/-5), and CON (122+/-3) rats (P<0.05). Thus , sympathectomy restores the natriuretic response to a high salt intake and prevents the development of salt-sensitive hypertension induced by sensory denervation, These data indicate that sensory nerves counterbalance the pr ohypertensive effect of the sympathetic nerves to maintain blood pressure w ithin normal range during salt loading.