Calcium channel blockers inhibit the antidipsogenic effect of central injections of zinc in rats
Rev. bras. pesqui. méd. biol
; Braz. j. med. biol. res;29(12): 1651-5, Dec. 1996. graf
Article
em En
| LILACS
| ID: lil-188449
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BR1.1
ABSTRACT
Previous data from our laboratory have indicated that acute third ventricle injections of Zn2+ elicit a significant antidipsogenic response in rats in three different situations dehydration, and central angiotensinergic or cholinergic stimulation. In the present study we analyzed whether this response depends on voltage-dependent calcium channels. Dehydrated (l4 h of water deprivation, overnight) animals received 2-mul icv injections of zinc acetate (Zn(AC)2; 300 pmol/rat) after pretreatment with the voltage-dependent calcium channel blockers gadolinium (Gd3+;0.03, 3.0 and 30 pmol/rat) or verapamil (VER; 0.027, 0.05 and 0.11 pmol/rat). Both blockers reversed the antidipsogenic effect of third ventricle injections of Zn2+ in a dose-dependent manner. After 120 min, animals pretreated with saline receiving Zn(AC)2 drank 3.10 ñ 0.57 ml/100 g body weight while those pretreated with GD3+ at the highest dose displayed a water intake of 5.45 ñ O.41 ml/l00 g body weight (P<0.01). Animals pretreated with the vehicle of VER receiving Zn(AC)2 drank 3.15 ñ 0.45 ml/l00 g while animals pretreated with VER at the highest dose receiving Zn(AC)2 drank 6.16 ñ 0.62 ml/l00 g (P<0.01). The antidipsogenic effect of Zn(AC)2 seems to be specific since the metal (same dose and injection procedures) did not modify food intake in rats after 24 h of food deprivation. It is suggested that Zn2+ exerts its antidipsogenic effect by activation of mechanism(s) depending on the functional integrity of voltage-dependent calcium channels.
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Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
Zinco
/
Angiotensina II
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Bloqueadores dos Canais de Cálcio
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Acetilcolina
/
Desidratação
Limite:
Animals
Idioma:
En
Revista:
Braz. j. med. biol. res
/
Rev. bras. pesqui. méd. biol
Assunto da revista:
BIOLOGIA
/
MEDICINA
Ano de publicação:
1996
Tipo de documento:
Article
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Congress and conference
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Project document
País de publicação:
Brasil